The Omaha version used to be very profitable until late 2017, but then, the rake was increased, and the jackpot share to be won was decreased. I never liked the Holdem version much; note that it requires a significant change in ranges due to the benefit of going all-in with suited (semi)connectors due to their straightflush potential, which weakens your range and requires you to remove the weakest of offsuit/disconnected hands that you'd otherwise shove due to high card strength.
Backdoor royal flush draws should usually be played in the Omaha (almost always semibluff them if no one has shoved before you); 4-card royal draws should be played absolutely always, of course.
I'm unaware of the current reg/amateur ratio; the AoF games used to be very reggish in 2017 ( (2-3 regs per 4-max table even at 0.10/0.25 Holdem and 0.25/0.50 Omaha).