New exhaust time has now arrived, just had good look & I have a pre 85 exhaust (Aircooled) on my 1988 water cooled engine

Why are there 2 different models as it appears to be a good fit? Will this have had any affect on the engine performance ?
So I have narrowed it down to 2 new exhausts, the VW speedshop OR La performance, which should I get??
Thanks