From my dealings w/ Sound Perfection, they don't typically budge from MSRP. The have sales from time to time, but unless you happen to be there during the sale and ready to buy, they are extremely unflexible.
To illustrate, my friend was recently in the market for a Lex. MC12B. We stopped by Sound Perfection and they had one, sealed in the box on sale for $7,000. He didn't have the money then, but raised it about a month or two later. We went back to Sound Perfection and they wouldn't budge on MSRP.
Same thing happened to me a few years ago when I was buying Paradigm speakers. I called them, knowing they were a dealer and asked what their price was for a Studio CC. No dice, full retail. I found the speaker the next day at a different dealer who offered a 20% discount.
Anyways, those are just my two isolated experiences, hopefully someone's had more success than I. When they do have sales, they list items at pretty good prices. To be fair to Sound Perfection, neither my friend nor I were regular customers who had any experience with them. Just two guys who wandered around their store a few times.
Paradise, however, seems more willing to work on price. I don't think 10% discount would be unrealistic.