I've used it. It just allows you to alter your connection settings easily. If you start fiddling with them write down the original settings before you start. Just in case you go too far and lose your connection and can't remember where you started from.
Found certain sites which require logging in(this one, my bank,etc)load faster if you drop the MTU. Try 10 at a time. Normal bb setting is 1492 but anyone on AOL should use 1400. You will find that a setting slightly lower than nominal usually works better. I wouldn't take too much notice of the "optimal" settings that DrTCP comes back with but it allows you to tweak them manually without having to delve into the depths of Windows.