[scotoap]

Add if you want a brushless combo, cheapest and IMHO the best value for money Losi Exceloron 13.5T (27Tbrushed ), 10.5T (19Tbrushed), or if you think you want quite a lot more speed, go for the 6.5T, I have this in my TRF501X; they are basically a cheaper version of the Novak GTBs from the looks of them and perform very well for just over the £100 (includes the ESC).
Also if you can afford it grab yourdelf a Spektrum, or other 2.4 ghz tranny kit (no more messing with crystals and a lot better controls for tuning to your choice; good luck, oh for these you will find some good deals new and used on the web and for sale sections of most RC websites including ours.