The 'vettes since about '98 are pretty bullet proof. It's a hell of a lot of money for what you get. I've got an
'02 Pontiac Firehawk that's got pretty much the same engine detuned (345 bhp/345 ft./lb. torque). It's my "good" car. The Boxster is my daily driver. The LS1 is one hell of an engine.
Having said all that, the Boxster is a great car too. After doing the rear speaker install, I can't help but think, "Why doesn't GM buy a Boxster, take it apart, and see what makes German engineering so great? It's is a damn well made car."
But, at the end of the day, you've had a Boxster. It's time you get the Z06. At worst, you can decide that you made a mistake, sell the Z06 and buy another Boxster. Right?
I can tell you that nothing brightens your day quite like putting the pedal to the floor on an LS1. The Boxster goes great. It's a great car. In terms of straight line acceleration though, it can't touch the 'vette. The Z06 probably has it in cornering performance too. I think the Boxster shines in braking though because of its lighter weight.
If you have any doubts, just listen to it (
60-120.
One thing I know is very different between the Boxster and the LS1 is the power band. The LS1 has a much narrower power band than the Boxster. You have to drive it much differently as a result. Besides, try to get 28 mph on the highway in a Boxster.