Which Sub? The new Monitor Audio BXW10 or NHT B10D

I am starting with a pair of Monitor Audio RX1s and building from there. I can't afford the Monitor audio RXW12 sub to go with my speakers, and these are my affordable choices since I also can't afford the Rythmic F12. I really am only considering these two subs at the moment. If we could keep the convo to these I would really appreciate it!
If you know where to look, you can get the Monitor Audio Silver Rx-6 for less than a pair of RX-1's plus either sub. The towers should take up less space because their footprint is the same or less than speaker stands for the RX-1s and you don't need subs (at least, not as much).

If you stick with the RX-1s, another approach on subs would be to get a *pair* of Mirage MM-8s. Just a few weeks ago these were going for $799 each, but there are ebay vendors which have them at $239 ea., free shipping, and a 30-day return period.

They aren't bottom-rattling subterranean subs. They are very usable down to around 36 Hz, which would give you at least another octave over the RX-1s. They are also tiny--a 9" cube that fits anywhere.

I have a pair of these subs that I use to fill out the bottom of a pair of Mirage OMD-15 towers. These subs are ideal for blending with mini-monitors. They use aluminum cones and passive radiators, have specially designed long-throw surrounds, and pack 1800w peak (300+ rms) internal power. They are also highly configurable to get the best blend with your satellites. They have continuous dials (not toggles) for volume, crossover (from 50 Hz on up), and 0-360 deg. phase. I/Os are strictly line level RCAs like the Monitor Audio BXW10.

I get a seamless blend with my mains and these MM-8s are very fast and have a transient response that easily blends with the 5-1/4" woofers in my OMD_15s. This is $1600 worth of subs for $478.

Ask around; two subs are better than one.