What RAWalker said about the accuracy (and resolution I guess). I dive a Shearwater Preadator on most dives but use an Aeris T3 Elite (hoseless) for some stuff. When I want to get real good RMV info I take along a transmitter and the T3 for gas usage info. You get much more resolution via the electronics. If I’m worried about cracking the transmitter off the first stage on a wreck or cave ceiling I put it on an HP hose and stuff it in a safe place.
As far as lockouts on the recreational computers, shouldn’t really happen to NDL divers or very light deco divers. Anything else and the recreational computers are useless, except for gauge mode for depth and time backup, but that would be for another thread.