The golden rule is don't ever glue the motor or bushings in!
OK I feel guilty about trying to gain a misinformation advantage - you can use slot-it hubs and any rubber tyre - proslots are choice (but diff to get hold of) so if you can get slot-it p3s they might hook up pretty well. Axles and gearings got to be standard so if you running a Fly use Scaly bushings (the nylon ones or sport ones) and sort out the front axles esp if its a stubby set-up. Glue everything in and get the body to float nicley.
Weight - you'll need some to give rear grip but not so much that you can't brake or accelerate - I use about 5/6g but I know some use about 10-15g. Weight is trial and error based on your own driving style.
Fly Panoz will be most peoples choice but Mick swears by the carerra panoz and he wins so there must be sommit in it.
Matt