[Perfectlap]

Reading those comments there seems to be a belief that a pre 987 Boxsters are on par with S2000's on performance. I don't think they are very familiar with the Boxster S. My local autocross like most others classify the cars on power to weight ratios. Base 2.5 and 2.7 Boxsters were grouped with the S2000.
Boxster S 3.2 and 3.4 987 were one class above running against the standard 996 3.6 Carreras and some of the older 993 Carreras. I regulary saw lap times from Boxster S (3.2) that at least matched and often beat the higher horsepower Carreras. Probably due to the fact that they didn't have long straights to make up ground against the more nimble Boxsters.

At any rate very few of those S2000 owners seem to have first hand knolwedge of any Porsches. So if I were you I would focus on what they like about the S2000 and not so much what they don't like about a car they haven't even driven. The best advice is from someone who has driven both in a track and autocross setting which I presume you are looking to do at some point.

by the way, the Boxster is not the "lowest" Porsche. An base Cayenne is the cheapest Porsche you can buy. Also, the Boxster sets the bar in the roadster category. I don't think there any other Porsches that can say the same.