veneers tend to be for asthetics i think, most guitars that have them seem to be emulating higher end guitars, like an epi les paul or a sterling axis type guitar.
saying that.. i have an actual axis and the maple on that is really just a cap, not so much a top, and it's a basswood body and maple neck. so who knows? i'm an EVH fan but i don't buy stuff just because it has his name to it, the thing with him is, the guitars he designs are incredible. have owned the axis and the peavey wolfgang, and play the fender wolfgang. all excellent. another thing about him is i don't think he does something for no reason when it comes to guitar design, if he has a maple cap on his guitar (at least the musicman) he must reckon it adds something