Stay away from an scr ( halcyon is one) go CCR, they are much more efficient on gas, lighter and have considerable deco advantage over an SCR unit.
The unit you chose is not the real problem, the problem with any rebreather is the training that you receive and how seriously you take it.. If you dive deep an CCR has many advantages over an SCR and if the control logic gets screwed up, you can then dive it as an SCR... so You can start at the best, and drop to the next level if you need to..
Of all the SCRs available, the halycon is probably the best (but its not an original design its working concept is almost unchanged from a rebreather that was designed in the fifties). The haycon is a variable scr in that depending on depth the dump rate will change and its also keyed to you breathing cycle, the main drawback is that you MUST carry multiple gasses, since a gas breathable at depth is not breathable at the surface(if you are diving deep), and you aren't always breathing the optimal mix.. For a device that has its roots in philosophy in breathing the right gas, The only time its true is at MOD and nowhere else, since it maintains a constant FO2 rather than a CCRS constant PO2.
Under 10k you really only have 2 choices that are readily available now, the Inspiration and the Prism.. The megladon looks like its going to be a good unit but its not readily available.
The prism is a nice unit but is missing some options I would like to have (that the inspiration has), but it also has a backup o2 monitoring mode that reads the cells directly - no power required. The inspiration is a reliable unit, If you are trained correctly, don't exceed your training limits and follow the guidlines you shouldn't have a problem... I have yet to see an info that any of the accidents were caused by the unit, everything points to diver error (or diver health), and many of the accidents were people with very little time on the unit. There are many more of them than any other unit around so I would expect it to have a higher number of accidents than any other unit.
Just because you can dive deeper tha 200 on OC does not qualify you to do so on a CCR. If you don't pay attention to details a CCR is not for you, an SCR is more forgiving, but some people should just stay on OC.
I currently dive an Inspiration (I'm an Inspiration instructor) and have enjoyed it (and its easy to travel with), I also have an Infinito by Powerbreath on order.. This was designed for military and commercial use.. Its starts around 18.5K...
