Here's a site with stats compiled from several different magazines over many years:
http://www.autosite.com/new/grabbag/perform/3814.asp

2.7L 5 speed Manual 0-60, s. 6.00
70-0 Braking, ft. 161.00
1/4 Mile, s. 14.60
Skidpad, g. 0.93
Top Speed, mph 148.00

The Boxter S is considerably faster, 0-60 in 5.3 and the 1/4 mile in 13.9 seconds.

The standard Boxter (by the numbers) is pretty even with a chipped Crossfire in acceleration and the Boxter is a bit better at road holding.

I like Porsche's a lot, the Boxter included. There's a guy here at work with a fairly new Carerra 4 and it sounds and looks real nice. They're grossly overpriced compared to some competitors though.