I am sure that the pan car guys asked this same question years ago when Tamiya came out with the first "touring cars".
It is all going to depend on if anyone else makes a car like the Slash. If they do, if it fits into the same class that already exists for the slash all over the country it will be around for a while. As it sits now it will be around for a few years at most.
The key to this is the spec formula, the vast majority of people want to do this to have fun, and they don't want to spend a ton of cash to do it.
I am not sure that the AE offering is going to take off like some think it will, it is pretty expensive. At my last race I saw 6yr olds racing the traxxas car as well as guys that are very fast in 4wd mod buggy. That is the key to class growth, something that everyone can have fun with, and they look so cool running around the track, and they did pretty darn well also.