I recently installed RE730s on my 91. Stock tire sizes on stock rims. The alignment was to 93 specs except Front Toe was set to 0.0 to decrease tire wear. Custom Alignment in Mountain View, Ca 650/961-5311 did the alignment for about $150. They are familiar with the NSX, have state of the art equipment, and their lot is always filled with Porsches for street and track. I was concerned immediately after the work, since the car now seemed to ride more like a Lexus than the NSX that I was used to. After reviewing the pre vs. post alignment settings with that was provided in the work report, it was clear that the difference was in the tires and not the alignment. After discussing this with Custom Alignment I believe that this can be attributed to simply having more tread on the tire (tread squish). The handling improvement, of course, is gradual as the tire wears, but when the old 'slicks' are replaced with new tires the handling will feel degraded.
In summary, I have no experience with the SP9000s and don't know jack about the effects of alignment settings, but thought I would relate my experience. If you would like to talk to an experienced individual about Street/Track alignment setups here in the Bay area, give Custom Alignment a call. They will set it up the way you request, and guarantee their work. No I am not affiliated with them, I just greatly appreciate outstanding customer service.