Found aome Ground Wire kit on Ebay that claims better perfromance..Any thoughts on these kits?...Do they really do anything?

check out www.groundfusion.com

I did the DYI, I didn't really noticed a big difference but the headlights are brighter.

http://www.scionlife.com/forums/viewtopic.php?t=29261

Do it yourself for 20 bucks.

you don't get a HP performance gain from ANY G.W. Kit. If they claim it, they're lying. I have a GW kit, and all it did was smooth out the idle - which is all I was expecting anyway, that's all I wanted. It now holds a rock steady 900rpm at idle as before the wires, it would fluctuate and stumble a little - bugged the ____ outta me.

But anyhow - that's about all a GW kit will do, smooth any non-problemattic very slight erratic action from the motor (that's not mechanically caused)

It won't provide any real gains but doesn't hurt to bling a little. Check out the buddy club condenser unit. It is a really nice setup.