Lee prefers his 511 but he wont publicly admit it because Tamiya stopped making 511 kits and still has to sell whatever 502 kits are left. 502 is still very good but I think AE has the best overall 4WD shaft 1/10 buggy design at the moment. 511 is tops!
Maybe Tamiya will come out with the next generation belt driven 1/10 TRF buggy to continue in the 511's footsteps, but who knows? Actually, Lee would probably know. But with the introduction of the DB02 it doesnt look as such. I'm holding on to my 511 until spares are no longer available.