Wilson WP 8 or Sonus Amati Anniversary?

Th quite WP 8's are dynamic as hell and have bone crushing bass. The top end is neutral and extended so results will be greatly determined by gear and cabling. The SF's are more forgiving and not quite as alive as the WP's. You can use tubes on the WP's to great effect as well. Cabling should be Transparent or MIT Oracle for best results:)

WOW! Completely different speakers! You need to hear for yourself. I would say the Sonus are warm, more colored. The WP's are cleaner, less colored. Sonus are wonderful, lush sounding speakers, WP's are more neutral. Both are great speakers.
I can't say about the Avalons, but the WP's don't sound at all like the B&W, IMHO. The B&W's might be somewhere between the WP's and the Sonus, leaning toward the WP side.
Don't trust my judgment though . . . you MUST hear for yourself before making that investment.

Cables choice is a determinant of whatever sounds and works best in your system.

Not what somebody else says "should be".

That shows a complete misunderstanding of the cables' role in a system.

Sounds like you've already made your choice considering you've posted an ad selling your Avalons with the claim you're getting the WP8s. Probably a sideways trade.