2 Rel T7s or 1 Rel T9???

I'm replacing a pair of Rel T2s in my 2 channel system. Considering a pair of T7s or a single T9. Looking for opinions on running a larger single sub vs a smaller pair. My room is smallish, 12x19. For me, it's about the music not a floor shaking experience.
Also - read the latest article about subwoofers in the Absolute Sound magazine, this month's. Everything I've read points to the superiority of two subs. Two 7's should be
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Thank you for your input and expertise. I am going with the pair of T7s! I think it makes good sense on several levels. Ben_wood, sorry to report, the T2s are gone on a trade.

Any suggestions for bass heavy recordings for sub run in period?