[firestorm]

What are (were) your existing surrounds? I have bookshelves on something like 30" tall stands, which haven't been a problem with two cats. Our son has never knocked them over, although he tried on a couple occasions (came close enough I almost screwed the stands to the floor or wall). The speakers are reasonably heavy though, plus the stands have a fairly broad base and I have them up against the walls. I didn't get the carpet spikes with the stands (they were used), but those would make the stands considerably more stable.

Just trying to open up some other options. Stands can be pretty pricey though. But, there are other options, such as hollow stands that you could fill with marbles, kitty litter, or other heavy material. Then again, I was working with what I had (speaker wise) and you have the luxury (or perhaps curse?) of more options.

Almost forgot... I've only seen one system with floorstanders in the rear, but there's no practical reason that they wouldn't work. It seems that people generally put the "rears" up higher than the fronts though, and you'll loose that flexibility with floorstanders. Unfortunately, our friends were soon separated (and subsequently divorced) after they got the surround system, so I didn't get much time with it at all and much of that was music. It was a Sony system as well, so I was more focused on the general sonic differences between his system and mine. I merely noted the choice, which, IIRC, was simply because the towers cost the same as smaller speakers + stands.