Have various brands, D&S, National Pride. JE Adams, Coleman.
For a basic vac you are really buying the shell and security features.
Coin Mechs, timers, and motors are pretty mutch interchangeable.
I would stay away from the 3 motor vacs. Not worth the trouble unless you have some extra revenue selection for the third motor. They don't suck any more because there is a limit to how much air can go thru the hose. (Law of diminishing returns) and you need heavier wiring and breakers plus relays.
Anyway, have about 15 Coleman combo units, (3 loactions) the big ones.
Unles there were serious financial consideations the extra cost with the bill acceptor option and heavy security features is worth it.