I just finshed putting my set of Z3 fenders on my '99 GS. I went with aerogear and the fit was perfect, no cutting or grinding required, it was a direct fit. I think they look great but I do agree that they will look shitty if they don't fit JUST right.
Regarding to the Aerogear VIS question: I've put a couple of sets of the VIS version on and I've always had to modify them, espcially if you have factory side skirts. Plus the VIS ones are 289.00 a piece, not a set. They are sold individually for the same price you can get the better fitting Aerogear pair.
Just my 0.2 worth though, do whatever you want and don't let anyone try and change your mind.
