You're never bored on your spare time when you're hooked on RC...
Here's some "how to's" if you wanna go all the way!
http://www.ymr.no/10ortips.htm
XX4s are easy to find on ebay, no problem!
Btw. if you're thinking X-5. Check out the X-6 as well! The X-5 is very good, fast & easy to maintain. You still can do good with most cars these days. The X-6 is WAY better than all those rear motor cars!!! I've seen the light!!! I don't believe too much in God, but boy do I believe in those Sinclair guys!
The best guys in the world will win with any equipment. But us mere mortals really need all the help we can get!