Check YouTube. Hobao makes their own upgrades and spare parts are readily available on the Hobao USA website, Absolute Hobbyz, eBay and direct from Hobao in Taiwan.
It's basically the 3 mentioned above and the Revo 3.3.
There is the HPI Bullet but it is a small 1/10 monster truck that is rather fragile from what I've seen and also the Tmaxx but that is an entire thread within itself.