HOGS are newish but very rapidly gaining a large and loyal following, apparently breathe very well, service kits openly available and well priced, if I were looking at a new set they would probably be on the top of my list, the money tree in my garden has died and I also service my own gear. ScubaPro MK17/25 1st, MK17 usually is used if diving colder waters although many report no issues with MK25 in colder water, with S600 2nd also has a very good reputation and a large following. I have dived an Aqualung Legend and liked it but was a little pricey for me. Atomic make good regs and all models apparently breathe the same, the differences between models, except 7LP ports on one of the Z2s, is materials used. Personally I use Apeks, FSR with XTX50s and DS4 with ATX40s. I dive both warm and cold, in my experience APEKS have been very reliable are relatively simple to service and I can get service kits easily. Most will recommend what they use there aren't too many bad regs made if any, it boils down to personal preference and conditions you dive. I like both primary and back up being the same, same breathing characteristics, same service kits. Good luck.