Monitor speakers pros/cons

Since your settings and set-up with the subs are likely to be ideally optimized differently for music and HT, you may not want to depend on them for your music reproduction if they're primarily used for HT. The best way around this is to go fuller-range on the mains, and push the sub response down in frequency so that they don't interfere with the music as much. For what sounds to me like actually a fairly large room size, and given your budget and dual-use intentions, I'd go floorstander on the speakers, and use the subs only for true sub-bass augmentation, or turn 'em off entirely when playing music. (Then again, I don't care about HT at all compared to music, and consequently don't even own an HT set-up [though I've sold 'em], so take my word only for what it's worth...)

Last 12 years, I've had 10 pairs of monitors and 7 pairs of floorstanders. Also used 10 different subs during this time. Until this year, the best monitor I had was the Sonus Faber Electa Amator I and the best floorstander was the Genesis APM-1. This was the only floorstander that was a TRUE full range speaker because of the built in 15" sub in each tower. All the rest needed subs to get the last octave of music or the LFE in movies.
My conclusion, you need a sub to get true full range (20Hz~20kHz) so why bother spending the money on the cabinet if you can spend it on higher quality drivers in monitors. The floorstanders are also harder to place, move, pack and ship if you decide to upgrade too. The cost of stands for monitors is minimal, particularly on Audiogon. Once you have good ones, you can keep them for all future monitors.
The REL subs are the way to go for both HT & 2ch because they have a unique Neutrik speaker level input that takes the signal from the power amp for seamless integration with the L/R speakers. It also has a line level input for the LFE channel from a HT processor that can be hooked up simultaneously.
Finally, my discovery of the year, a monitor that really goes down to 40Hz! (-1.5db, not -3 or -10db) The System Audio SA2K uses custom ScanSpeak drivers in a unique 14"Hx7"Wx12"D cabinet. Its sound bested the SF EA1 and with the REL sub beats the APM-1's. See it at http://www.system-audio.com/showpage.asp?siteid=2&id=312

Check out Verity Audio (www.verityaudio.com). They have
a monitor/Parsifal encore and a woofer unite that mates.
The reviews are always great and I see them, with woofer, going for
around $7500 in Audiogon.