This application hurt network performance overall, and didn't restore my system to its previous (better) performance when I asked it to return to the defaults.

I have a cable modem connection that gets me 6 Mbits/second over a wired connection to nearby internet servers, and I was interested in seeing if I could improve download speeds from distant servers. After applying the presets for "Cable Modem", I began getting only 4 Mbits/second from the same nearby servers -- a 33% DECREASE in speed. After asking it to restore the defaults, I started getting less than 3 Mbits/second -- a 50% decrease from vanilla Mac OS X. And it's a little disturbing that when I asked it to turn itself off, instead what I got was further slowing of the connection.

A nice idea, not ready for prime time.