I just listened to an 800 connected to two DSP5500's. Then compared another 800 with 803's 802's and 801's.

First Place: DSP5500
Second Place: 802's
Third Place: 803's
Bringing up the rear: 803's

The 5500's had incredibly fast bass response on the low end and excellent transparency in the mids and highs. I was very impressed. The DSP6000's IMO look better and have just a tad more bass. It's would be hard to justify the extra money.