Thiel 2.3 behind couch or B&W 607 Bookshelf for rears.

I've been working on my theater.

For my rears, I have a pair of Thiel 2.3 floor speakers.  However the couch is a very large L-Shape and both speakers are fully blocked.

I've been considering a pair of bookshelf speakers, so they could play unobstructed.  One pair I was considering is B&W 607s.  

Since these are rears...would the B&Ws be a good trade off? in a 5.1 arrangement?

The other question....if I wanted to go from 5.1 to 7.1.....  both the Surrounds and Surrounds Backs are behind the couch.  Which are used more?  and if I had Theil floor and the B&W bookshelf, which should I use for Surround, and which for Surround back?

Feel free to join us over on the Thiel Owners thread. There a few owners of the CS 2.3 that can offer solid advice on your HT situation. I have owned both B&W and Thiel Audio speakers. I see no issue using the B&W as a back-fill/surround option.  Happy Listening!
Thanks all.  I ended up with a pair of scs2s.  Something to say about Thiel all around.  :)

yeah the 2.3 tweeter would shoot straight into the couch and probably not sounds right. I tried to use a pair of B&W 803s as rears when i had them and ended up moving to a diepole wall mounted speaker (focal).