I have owned and raced - HPI Proceed, Serpent Vector 2000, Serpent Veteq, Mugen MRX2, SMP Slide.
Out of all of them, for where I live I prefer the HPI. The main reason is that out of all of those cars, HPI is the only car I can get parts for locally. If parts support is not a problem, I think the Veteq is the best handling car I've driven. It is tricky to get set up right, but once you do, there is no comparison. I found the Mugen and SMP cars to be the most durable, but if you do happen to break an SMP part, be prepared to pay. I haven't driven an MRX3 yet, so I can't comment on that.
I have also driven (but not owned) a Neo car. That car seemed to be easy to adjust and easy to drive. It was every bit as fast as anything else I'd ever driven. You have to remember that any of those cars is too fast for any track. But, once you get the car dialed in, I don't think you could go wrong with any of the cars out there today. I have even heard good things about the GS car, if that kind of thing interests you.
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