Which type of speaker for narrow room


I plan to upgrade my speakers soon and would like to get some opinions as to what type of speaker would work best with my room. I have a long narrow room, 24x10x7.

Should I chose a bookshelf & sub or go with a tower speaker? My local dealer recommends B&W as they say it will go great with my Rotel stereo gear. So I'd probably be looking at either a CM5 or CM8/9. If you have any other suggestions, feel free to let me know. Thanks in advance.
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