Test rides are great, to a point, kind of like dating, but you'll never know the true character until you marry it. Even so, give it as good of a ride as you can, and make sure the fit is right.
I'm confident that you would be happy with bikes from any of the brands you listed. They are all good trail/XC race bikes that you can justifiably upgrade when and if necessary.
My ride is a Giant NRS. I bought the frame off eBay - how's that for a test ride? - and hung my hardtail parts on it. I'm enamored with it and will never go back to a hardtail. The NRS has minimal small-bump sensitivity, but its 3.75" rear end soaks up the biggest hits I ever ride over. As an XC racer the NRS is wonderfully efficient and seems to find the right compromise between efficiency and travel.
Even so, I could be just as happy with a comparably equipped Fuel, Sugar or FSR.