When I got into gas a short time ago, I was advised that the OFNA Hyper 8 was the best bang for the buck. Only two or three people run one at SRH ("Speed Racer's Hobbies" soon to be renamed to "Speed RC" in Richardson) though. I'm not sure if the parts support is there right now, you'd have to check.
I ended up with an Xray XB8R because my friend had one. It made it easier on my wallet at first because he was letting me share his starter box and glow plug stuff.
Most people run an Xray XB8 or TQ at SRH. There are a handful of Mugen's and Kyosho's though. We don't really suffer parts shortages to the best of my knowledge because RC America (Xray distributor) is in town. If you can drive decently enough to avoid the spectacular crashes into cinder blocks or landing upside down it's rare to break anything anyway. These cars are tougher than electric cars.
Anyway this is not intended as an ad for Xray. My advice is that you go to the track and talk to the racers. Check out the hobby shop wherever you plan to run. If it's SRH than Danny and Ty (the owners) are very friendly and helpful. Ask the same questions you are asking here. Danny has a Mugen ProSpec and Ty runs a Kyosho (not sure on model type). Between them and all the racers you will get the gist of why they like each vehicle.
My objective when getting into any class was always to see what the fast guys were running. It's always good to have someone to copy or talk with rather than struggling with a car no one knows much about setup wise.