I can do a full service on HOG regs (1st, 2nd, and octo) for around $100. Including parts.
And the HOG's only require service every TWO YEARS.
An inspection is recommended at a year and what I do for that is checking pressures and adjusting them if necessary (mine did not need it), inspecting hoses, mouthpiece (will replace if necessary or asked to),inspecting seats and if necessary change (again mine did not require it), and give everything a good cleaning.
I charge $25 plus parts if required plus shipping back to the owner. So with me anyway an inspection at a year and a rebuild at two years would run in the neighborhood of 150 bucks including shipping back to the owner. That's every 2 years though.
As for comparing them with ScubaPro or any other brand, I own regs by HOG, Oceanic, Sherwood, US Divers, and ScubaPro. I've used regs by all of these plus Atomic, Dive Rite, Aqualung, Zeagle, and Mares. None of them are any better as far as quality of construction, finish, attention to detail, and how they breathe. As an instructor I've taken every opportunity to use as many different pieces of gear as I can to better serve my students. The only thing I've not used is a double hose or a rebreather. Yet.
I'd say my HOG's breathe better than any reg I've tried and are more comfortable. And the fact that users are able to take a class to service their own regs and buy kits without going the back alley route along with the price point make it a no brainer and why I am in the process of selling off my other regs and replacing them with HOG and Edge. I have kits for my other brands and in a couple months I'll be doing the annual service on them and then selling them. Gonna be some good deals on some good used regs this fall.
ScubaPro, Aqualung, etc are very good regs. Their names are well known. But like a Harley you pay for that name. I had my bike inspected last week and was looking at some of the new Yamaha's and Kawasaki's. Two I liked are set up exactly how I'd want with accessories and all. Both are around 9 grand. A comparable Harley would be in excess of 17. For a bike that is more expensive to maintain, service, accessorize, and insure. And IMO the quality is no better. Regs are the same way. Pay for the reg not the name and you can save big.