There is a lot more to it than just brand - some of there stuff is ok, but some of their stuff is not.
They are into plastic buckles on their harnesses and bungeed wings are a big NO in a cave. Their plates are deeper than some and flatter than others and they tend to have a lot of perimeter holes (neither good nor bad) left over from OMS's prior preference to use metal to metal connections on just about everything - another big NO. Their D-rings use heavier diameter wire than most - which is mostly a matter of preference. They are stonger (the need for that is arguable) but the downside is that a bolt snap has to open more to attach and detatch - which could be more of an issue with a slightly corroded boltsnap. I would say it is both a pro and a con.
So in short, even their basic one piece harness will need a new buckle, their plates are ok and their wings are ok only if you get a non bungeed model, stay away from dual inflators, and replace the ungodly long corrogated inflator hose they come with. Their stuff is overall not really cave oriented and is by no means superior to other stuff you can get for the same or less money. You would be better served by buying from dive-rite, deep sea supply or some other company with a better feel for the pulse of the cave community.
I would not buy an OMS reg. Ever.
On the other hand, the OMS Slipstream fins are excellent.