Brent Butterworth tested the Rel T7 in the January 2013 issue of Sound&Vision magazine. Check to see if its up on the web.
The Rel T7 has an 8 inch driver and a 10 inch passive radiator. With the REL T7 Sumiko and REL recommend connecting your front left and right amp channelsto the T-7's speaker level inputs, instead or in addition to using the sub's line level inputs with your surround processor's subwoofer output.
Sound quality is certainly good, however, for $1,000 I would be looking at something from Rythmik. Quite small and rather light at 34 pounds.
I know there is a REL following. For them the T7 makes sense.
The review does not appear to be online @Sounf&Vision yet.
One finding is that using CEA 2010 guidelines the Ultra Low Bass measured 97.7 db from 20-31.5Hz. For $1,000 I think there is more to be had. I would start by comparing the T7 to Rythmik.