Buying new engine or engine kit in next couple of days need help deciding..

Here are a number of sites on ebay and other dealers....Please give me some feedback on what you know about them....Also these sites might help for someone that is looking to get a kit for them selves....

80cc motorized bicycle bike engine kit centrifugal dual - eBay (item 260454577472 end time Aug-27-09 00:23:57 PDT)

Motorized BIKE GAS ENGINE replace 80cc motor silver EPA - eBay (item 150366608310 end time Aug-27-09 12:34:46 PDT)

REPLACe 80CC BICYCLE gas MOTOR ENGINE NEW black EPA - eBay (item 190322664039 end time Aug-17-09 12:29:34 PDT)

UPGRADED 80CC BICYCLE MOTOR ENGINE KIT MOTORIZED BIKE:eBay Motors (item 170374270892 end time Sep-19-09 17:42:51 PDT)

80cc bicycle engine kit EPA Certified

Grubee SkyHawk GT-5 80cc Bicycle Engine Kit EPA Certified BikeBerry.com

Bikinglane.com - High Quality Bike Engine Kits and Electric Bikes at a low Price!

everydaymotors.com

Check them out and let me know what all of you think...
Thanks
John-John