Chuck,
I'm not real qualified to answer this one; no experience, only theory, but my thoughts are:
The 3200 would be better for part throttle driveability not just because of the lower stall speed, but because the higher STR would make it feel even tighter than a typical 3200. With slicks, it might even give you better 60's at the track; it may put too much of a shock to the tires for drag radials to get a perfect bite. It would probably lose out to the SY3500 on ET and mph though.
If overall 1/4 mile performance is more important than street manners, go with the SY3500. I just expect it will feel sluggish at low throttle openings with that low STR. Quite a few stroker guys run it, but they usually have low end torque in abundance.