I have the Advantage Arms conversion kit for my Glock 19 gen 4 and honestly, I wish I didn't buy it.
I don't know anything about the RSU, but the AA one is very finicky with ammo type and 9mm is not that much more expensive during normal times than .22.
I guess, right now, it's nice being able to shoot .22 since 9mm is hard to find at a decent price, but if I could do it again, I would pass on it.