I've had the chance to do an A-B comparison, in my home, of the B&W Signature 805 and the Quad 22L. The Quad 22L is a very nice speaker, well made, beautiful finish. It exhibited nice balance and good low-end power.
However, the difference in detail, smoothness and articulation between the 22L and the 805Sig was HUGE. The best way I can describe the difference is to say that if the 805S sounded glassy-smooth, the Quad 22L was like sandpaper. What I mean is, vocals on the 22L were grainy, and a little more harsh, while the 805 Signature was so smooth and pretty-sounding.
It's easy to look at the 805 Signature and think, "what am I getting for $3500?" But listen to them next to the $1700 Quad 22L, and you'll get an answer very quickly. By themselves, the Quads sounded good, but once you hear the 805 Signature the Quads sound unacceptably grainy. And, by the way, if placed properly the 805S has as much low-end grunt as the Quads - it's amazing how much range that little bookshelf has.
I realize you asked about the 805, and not the 805 Signature, but I've owned the 805 as well and I'm not sure you'd be happy going to the Quad 22L from the 805. The 805 enjoys much of that upper-end sweetness that the 805 Signature has, so if you enjoy that part of being an 805 owner, you'll miss that with the Quad. The only thing the 22L will give you, above the 805, is low-end power.
I agree with Vaystream, in that you should check your cabling and especially your speaker positioning before giving up on the 805. In my experience, they are VERY VERY sensitive to positioning, and can go from bright to beautiful and bassy with proper toe-in and wall proximity.
Hope that helps a little,
BCGator