I own a couple of lights with electronic switches. The only one I use on a semi regular basis anymore is a Zebralight H301. Sometimes I use it every night for a week or two straight. Sometimes it doesnt get used for over a month. Guess what happens after a month if I forget to lock out the tailcap. Yes, seriously.
To the OP - very good question. I don't like parasitic drain. When it is very well managed, it is nothing to worry about (lights like the Fenix TK41 have excellent and very low drain - basically negligible), but some others are really bad. The NITECORE EA4 and EA8 have very high drain, especially if left on 'standby' with the switch flashing, and even if you use the built in 'lock-out' mode it is still higher than the TK41.
I think the best multi AA light with no drain would be the Fenix LD41. 4xAA and a mechanical switch for no drain and no need to unscrew anything.