using ace/5 in a single deck game is probibly better than doing nothing at all, which is worth considering, but you wont expect to win money, and if you do find some great game where you do it will prob be a break even game basically.
think of it like this, if you cant handle a regular card counting system, go ahead and use the ace 5 because you will be losing less money than using no system at all.
then again, why you woudl even learn to use it to lose money is kinda a mystery