I have the second generation 803 Diamonds with a 4Bsst, BP-25 and BCD-1 and I couldn't be happier. I also auditioned the PMC OB1i and the 804 Diamonds at my house. At the dealership I auditioned the former plus Thiel CS3.7 and the 802N. The dealer set these up with the 4Bsst2, BP-26 and the BCD-1 so I would have as close a comparison as I could get. They were all great and if I just listened to classical I might have gone with the PMC, but I listen to more Jazz, Bluegrass and Pop with some good ol' rock and roll mixed in. The vocals plus the Diamond tweeters sold me and the base was sufficient for my taste.
Personally I don't find the combination too bright but I like detail. I think you will find the sound sweeter than some of the reviews suggest, or at least I did. I spent several days at the dealer narrowing the field for what I wanted to bring home. After purchase I did find the 803 Diamonds too bright for the first few weeks but they smoothed out nicely. Currently I run a balance cable from the source to pre-amp and a modest priced cable to the amp (saving nickels). I use the Bryston power cords.