Hi Jeff,
Now I'm almost wishing I had tried that pair of tube amps I almost bought in January. They were a pair of Cary 572SE monoblocks that had the $1K upgrade to 300SE monoblocks, running 300B power tubes. The owner, who had the mod done, swore the sound was much better, but it did decrease the power output. I think it cut it from around 22 wpc to about 15 wpc if I remember correctly. My room is similar in size to yours, but I didn't feel 15 wpc would drive my Strauss. My current amp is 300/600 wpc into 8/4 ohms, and can tightly control the 10 inch woofers.
Regards,
John