The BMI was always a favorite - they even made a few more this last year but you'd have to call them to see if they have any left as their website is not up to date. Also check out Penguin RC. They still sell the P5500 for TC3. It is a killer chassis. Both are good but Penguin will still have parts support. And Diggity Designs also makes a converstion kit but you have to buy the whole kit. So IMHO the best aftermarket in 2006 would be the Penguin chassis. I own both the BMI and The Penguin.