Do fuel tank additives really make a difference?

[Lease-V-cross]

Makes ya wonder.
I mean most of these products that you're instructed just to dump into your gas tank are $3.99 on up depending what the additive is supossed to improve.

Gas treatment?
Engine cleaner?
Police repellant?

Well........ok........maybe not that last one.

[Green Dragon]

Some swear by them but not me. Just use a quality fuel to try & keep water out of the gas tank.

Bob