I remember reading a review years ago about the big 350 watt per channel Crown. It was paired with big B&W's. The Crown was rated poorly and not musical.
4 year old K2 is a steal for 400$ - if it's in fair condition of course.
The K2 is absolutely world class for bass but may not be adequate for full range to pair with the 802. I use it for my Wilson Audio WHOW subwoofer, where it is absolutely fantastic.
If you consider biamping the 802 (is that possible?) use it for the bass. If not you may look elsewhere.
I owned 801 sereis 2 for years and in my opinion it would outclass the Crown amp ( i also owned crown before ). I used and would suggest ( used Threshold s/300 ) ,s/500/ sa-1 monos etc. Exceptional amp non fatiguing very well balanced sound ( with great slam ) . They come up occasionally on Audiogon...
At $400 it is a good deal but overall the B&Ws will sound better as you mate them with a better high current SS power amp. Another entry level choice is Bryston or the Krell KAV-250, much more than $400 but you can upgrade later. the point being that you could use the Crown if that is all you budget allows for right now.
Remember, this is a pro amp designed to power speakers, instruments for bands. For HT, it would be a great amp for passive subwoofers (I have two) as it gives a powerful and crisp oomph for the bass. I'd agree on looking at Bryston to power those B&W's; Classe's great too as well as CineNova Grande.