Good choices, I'll give you my 2 cents, I'm a downhill racer so that is wheremy backround and knowledge come from.
The demo's are excellent bikes! They have a mid height bb, which I believe is also adjustable via rear shock mount. Good bike for everything all around, a bit long for really tight technical stuff.
Glory, again amazing bike, but they are heavy, I mean 13.5 pounds for frame and shock alone, they're very stable bikes, and the suspension is top notch, but they are cumbersome, not what you want in a technical course.
I would stay away from the ironhorse, they no longer produce the sunday, so if anything breaks or goes wrong, it will be extremely hard to replace, absolutely amazing bikes however. T
he Commencal is a great example of a bike to do it all, adjustable geometry out the ying yang, light, flickable everything you want, great pedallig to. If you were to get one i would suggest looking into the latest generation models (2008 +) as they have a bit more travel (bumped to 8 inches) and will be a bitmore forgiving.
Now I'm not sure if you're open to oher ideas, I personaly ride a Devinci Wilson, great bike, lots of adjustability, has that light feel but still gves confidence when you feel in need of a plow bike!
Other then that, maybe look into some of the vpp platforms, like the intense socom or the santa cruz driver 8.
Pm if you'd like to talk further.