I own cars powered by both, and when stock, the 3.0 seems to have better low end torque.

SS 3.2 is the champ because they rev so easily; especially when using an earlier non-Lambda CIS. :)

if you "expand" a 3L., you still have the CIS issue vs. the ability to eke out a few more hp with a modified chip for the DME -- see the 2 responses just above my Bingo comment on the last page.

if you are going to increase displ. - you can easily go to 3.4L with the 3.2 - and even a tad higher - it is not a cheap way to get hp.

then there is the issue of seeing high Et-OH levels in gas in the near future...

so the 3.2L wins on all of these motor issues:
1. low buck power increase
2. high buck power increase
3. lower emissions, stock
4. near-term future fuels compatibility

Non-motor issues:
5. easier to sell off heavy luxo-barge crap to achieve light wt. than to do other things (low buck perf. increase)
6. better brake system

the only reason to go SC/3L would be if the price were much lower - then you have to quantify the value of the benefits

Much of the perception that a SC 3.0 is a quicker more responsive car is the comparision between a 3.0 CIS car that has had it fuel mixture richened up increasing the low mid rpm throttle response, and a completely stock 3.2 that by default runs a stoichiometric lean 14.7:1 afr at low and mid rpms, which creates the perception that the car is not as responsive, heavier and slower. Stock 3.2s have have the sub 4000 rpm lag. Once you chip it though, the lag is gone, the car feels 500 lbs lighter, and has much more throttle response, closing the response gap between a 3.2 and 3.0, while still getting 18-28 mpg city/hwy. In fact I can chip a car to run like a 3.0 with the CIS adjusted rich, and make it respond as such, basically something like a European car, running open loop, but the emissions and fuel efficiency would go out the window.