Hi all, since I started this thread I wanted to give a quick update with some long term ownership info.
First off, I wanted to address using the Geo 4 for planned decompression diving with accelerated deco. It will work; however it is not a great tool for this. The main problem is that gas switching (and therefore practicing gas switching sequence) can only be performed on this unit while underwater, and the sequence and duration of button pushing is not at all intuitive. It was troublesome enough for me that after a dozen dives, I gave up. I now only use this unit as a backup in gauge mode if the dive plan will involve gas switches.
I also wanted to know exactly what would happen if the computer got “bent”. So, I intentionally brought it as a ride along on a planned accelerated deco dive, but without performing gas switches on the unit. The good news is that even when violating multiple stops, the computer continued to function and display deco instructions all the way to the surface. The bad news is that once on the surface it locked into gauge mode. If the diver is so bold as to do a dive again before the lock out is cleared, then the unit will function in gauge mode, but it will be incessantly beeping at you for the entire dive. It was annoying enough to make me cut the bottom time short.
Lastly a note about Huish customer service. After a little less than 2 years, the top left button ceased working. This is the one that allows you to enter dive mode manually and change settings, etc. From the bad mouthing of Huish customer service I’ve seen on this site, I expected it to be a challenge to get the unit repaired at in any sort of reasonable time frame and cost. To my surprise, I found the experience to be quite the opposite – the customer service was fantastic.
I emailed Huish with my problem, and within an hour I had a reply from Kyle at Huish that since my computer was still within the 2 year warranty terms, all I needed to do was fill out an RMA form on their portal, send the unit back to HQ in Salt Lake City, and they’d send me back a new one free of charge. The form was easy to find and instructions for sending the unit back were clearly spelled out. I tracked the shipment to see that it had been delivered to Huish on Feb 22, and got a notification from Huish advising the same. Today I had a new Geo 4 sitting on my front porch delivered via first class mail. I can’t complain about that.