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@Josh the diver I think you'll get a lot of the same advice from the same people.
My opinion is take Mod1 before you buy a unit with very few exceptions. You are not qualified to judge a unit in the water until you have at least dealt with the course. Pick the instructor you want to use first, then pick a unit that is close ish to what you think you want. I.e. if you want to dive a Meg, taking a Fathom course from @kensuf is good enough because the Fathom is basically a mCCR Meg, but you're getting instruction from Ken. After that course, you can then dive a Meg and see if it makes sense to you.
MOST rebreathers are generically similar so if you take a course on a unit with OTS counterlungs, it should dive pretty similar to all of the other OTS lung units out there and then you make your decision based on what your buddies dive, if there is a specific differentiating factor to a unit that brings it ahead of the others, deals on a unit *i.e. I would never have chose to dive an old Meg, but one was given to me, so that obviously changed my course*.
Now. The Liberty is a really neat unit and despite having a lot more "stuff" inside of it is actually no more complicated at a fundamental level than anything with a DiveCAN on it. What does that mean? Essentially all eCCR's currently sold are using CANbus technology to deal with the electronics. Shearwater is the big boy, but they were nowhere near the first. Poseidon has been using their own CANbus for a really long time, as have APD, and several others. This is the same technology used in your car where there are individual modules that have two-way communication for data validation. Using DiveCAN terms because Shearwater has done a better job of explaining how theirs works. In the simplest units, there is a a central computer *SOLO with DiveCAN* that is the hub for all data. It receives data from the oxygen sensors, sends signal to the solenoid, sends data to the handset and receives changes from the handset. Most units are only using that function, however it can also have ambient pressure sensors, high pressure sensors, CO2 sensors, myriad of other things that it can process. Most of the units also have an OBOE board which is a separate canbus system that runs the monitor *HUD, NERD, whatever is spitting out O2 data that is not the controller*. The SF2 for some reason still uses analog communication for this, but I suspect it's because it wouldn't fit in the head. What is important to note here is that on most units the SOLO and OBOE are both reading from the same sensors. O2ptima has one non-shared sensors and the Revo is weird.
The Liberty has chose to use redundant SOLO equivalents instead of a SOLO/OBOE concept. Each SOLO has independent O2 sensors, He sensor, computer brain, monitor/controller, solenoid, and pressure sensors. There is a data bridge between the two sides and the first one that is turned on becomes the master, the other the slave. The nice part of this is that if one side fails, you still have a fully functional rebreather and everything is modular so you should never have to send the head back for service unless you bugger up the threads or contacts *which is operator error, the unit can't do that to itself*, everything else is swappable modules.
So is it too complicated? I don't know, it's quite complicated, but I think it's a lot less bad than some of the other units out there in terms of what it can do and how it works. Is it better than an mCCR? It depends. I don't like CMF's and much prefer needle valves, but I also much prefer to just have a solenoid and call it a day because the solenoid can actually support life if it is functioning where the CMF's can only preserve it *passive injection, so it buys you time, but if you're working it will still fall*. I do have a mCCR with leaky valve which will get swapped to a needle eventually so it's not that I have hard and fast rules, it's more personal preference.
So what exactly about the Liberty has you wanting it? What other units are you looking at and why is the Liberty leading the pack?
My opinion is take Mod1 before you buy a unit with very few exceptions. You are not qualified to judge a unit in the water until you have at least dealt with the course. Pick the instructor you want to use first, then pick a unit that is close ish to what you think you want. I.e. if you want to dive a Meg, taking a Fathom course from @kensuf is good enough because the Fathom is basically a mCCR Meg, but you're getting instruction from Ken. After that course, you can then dive a Meg and see if it makes sense to you.
MOST rebreathers are generically similar so if you take a course on a unit with OTS counterlungs, it should dive pretty similar to all of the other OTS lung units out there and then you make your decision based on what your buddies dive, if there is a specific differentiating factor to a unit that brings it ahead of the others, deals on a unit *i.e. I would never have chose to dive an old Meg, but one was given to me, so that obviously changed my course*.
Now. The Liberty is a really neat unit and despite having a lot more "stuff" inside of it is actually no more complicated at a fundamental level than anything with a DiveCAN on it. What does that mean? Essentially all eCCR's currently sold are using CANbus technology to deal with the electronics. Shearwater is the big boy, but they were nowhere near the first. Poseidon has been using their own CANbus for a really long time, as have APD, and several others. This is the same technology used in your car where there are individual modules that have two-way communication for data validation. Using DiveCAN terms because Shearwater has done a better job of explaining how theirs works. In the simplest units, there is a a central computer *SOLO with DiveCAN* that is the hub for all data. It receives data from the oxygen sensors, sends signal to the solenoid, sends data to the handset and receives changes from the handset. Most units are only using that function, however it can also have ambient pressure sensors, high pressure sensors, CO2 sensors, myriad of other things that it can process. Most of the units also have an OBOE board which is a separate canbus system that runs the monitor *HUD, NERD, whatever is spitting out O2 data that is not the controller*. The SF2 for some reason still uses analog communication for this, but I suspect it's because it wouldn't fit in the head. What is important to note here is that on most units the SOLO and OBOE are both reading from the same sensors. O2ptima has one non-shared sensors and the Revo is weird.
The Liberty has chose to use redundant SOLO equivalents instead of a SOLO/OBOE concept. Each SOLO has independent O2 sensors, He sensor, computer brain, monitor/controller, solenoid, and pressure sensors. There is a data bridge between the two sides and the first one that is turned on becomes the master, the other the slave. The nice part of this is that if one side fails, you still have a fully functional rebreather and everything is modular so you should never have to send the head back for service unless you bugger up the threads or contacts *which is operator error, the unit can't do that to itself*, everything else is swappable modules.
So is it too complicated? I don't know, it's quite complicated, but I think it's a lot less bad than some of the other units out there in terms of what it can do and how it works. Is it better than an mCCR? It depends. I don't like CMF's and much prefer needle valves, but I also much prefer to just have a solenoid and call it a day because the solenoid can actually support life if it is functioning where the CMF's can only preserve it *passive injection, so it buys you time, but if you're working it will still fall*. I do have a mCCR with leaky valve which will get swapped to a needle eventually so it's not that I have hard and fast rules, it's more personal preference.
So what exactly about the Liberty has you wanting it? What other units are you looking at and why is the Liberty leading the pack?