All depends on what you want to do more. The Tamiya is completely limited to smooth surfaces so the Slash would definitely be more versatile. It will also be faster, more durable, and I think parts will be easier to get. Pricewise, these 2 should be pretty much the same. As for running all season, no contest, the Slash since it is waterproof. If you just want to drift on the other hand, then I'd get the TT01.