My brother in law (silvergsx) has these speakers. They are far and away the most capable $1,000 speakers that I've ever heard. The competition at this price are bookshelves that can't touch these speakers dynamic capabilities, bass response, and staging.
These speakers are just as much, or more, for 2 channel stereo as they are for home theater. Their designer, Danny Richie of GR Research, is a 2-channel only guy. Yes, for full range sound into the 20hz range you will want to use a sub, just like any other speaker that doesn't giant bass drivers. Bass is handled by 2 6.5" drivers in a sealed box, which is very tight and easily goes down to the mid 30hz range in a mid sized room, and doesn't have the boomy residue that you would get with a ported enclosure.
I'm sure the Strata Minis sound good as well, but they are no longer available, and when they were, they were twice the price of the X-Statics.
If you're in the market for a nearly full range floorstanding speaker for $1k that plays far out of its price range, I would recommend taking a closer look at these.