B&W 803D - Best amplifiers to drive them


Hi!

I actually have a few questions and I would really appreciate your wisdom on them:
1) 803D versus 802D - other than prize and size, is there is significant SQ difference, or if under budget constraints one settle for the 803D as they are 'almost' there?
2) Used 803D, how does one test a 2nd hand used speaker? Is there any way one can tell other than listening (auditioning) and visual inspection? Are there any key look outs?
3) The main question - which amplifiers drive the 803D the best? the rating says 50-500 watts, but that is a huge range at 8 ohms!!!!

Please do let me know
Thank you.
K
kelpie
Thank you all. And Mark thanks for the specific responses to all questions. Appreciate all your help and advice.
Kelpie, I owned the 803d for about 2 years and loved them. They do like lots of power though. I originally had a McIntosh MC352 connected to them and it sounded great. I bought a second MC352 and biamped them and they sounded even better. I finally purchased MC601 mono blocks and they sounded like a brand new speaker. The bass that I didn't know was there came right out.

I liked the 803d's so much that I deceided to move up to the 802D2's, I think they are worth the upgrade, though both are very nice speakers.

When I went to the dealer to purchase the 802D2's the dealer had a pair of PMC EB1i's there to demo against. There was no contest to the sound I heard coming out of the EB1i's. I liked the PMC's so much I purchased them on the spot. I have since purchase another pair of speakers but love them all. They all sounded great. It was only when I A & B'd them next to each other that I really had a preference.
I upgraded from a used pair of 704's that I really liked to a used pair of 803d's a year ago and then quickly began to ask the same question. I was using the Rotel 1070 seperates set that were a perfect fit for the 704's, but found myself wanting more. After looking around and becoming confused with all of the options, I settled on a used Accuphase E-450 integrated and could not be happier. The sound is smooth, detailed at any volume, never induces fatigue compared with previous equipment and I can't imagine the speakers sounding much better. They simply come to life. Have matched it with the Oppo BDP 105, Apple TV for streaming and TV, and an Accuphase t-1100 fm tuner and am going to retire with more music options then I'll ever need. I'm off the gerbil wheel for good, or so my wife tells me.
The size of your room will influence the amp. I have the 803d and use a Classe CA2200. Previously used a Krell KAV2250, but the Classe is a bit warmer. Pre is Krell KSL. Also used a VTL 5.5 which was very good. Room size is 16' x 23'. Generally speaking, you'll need some good quality/good current power as noted in previous post. Hope this helps some.