I did the yeah racing conversion on both my Durga and 501x. The stock attachment is retarted. Both cars had massive wheel wobble. With the conversion, both cars have wheels that turn true as can be.
I used the HobbyPro 5 spoke ebay wheels on the Durga, and they did widen the rear track.
On my 501x, I use Dark Impact wheels. Someone on the Durga thread told me car wouldn't handle right with them, but they are just about the same distance off the car as the stock wheels were and the car handles fine.
