I know the timer can be switched on/off, the guy selling it says everything works and he sent me some pics today and it looks in pretty good condition
games are - Super Mario Brothers 2, Gauntlet, Tyson's Punch Out, Double Dragon, Teenage Mutant Ninga Turtles, and Contra. (which I would say are some of the best options for that system)
he is asking 400$ OBO