Did someone say Ultra Towers??
I own the Ultras and I'm very happy with them. I haven't heard your other choices tho so I've no point of comparison between them. I know SVS' customer service is about as good as it gets. I've had them replace a grille, a sub amp once and someone here recently got a new Ultra woofer shipped, free of charge to replace one that had a slice in the surround. All out of warranty. Then there's their 45 day customer bill of rights, etc, etc. I knew if I didn't like what I was hearing they'd take 'em back and pay for the return shipping so no risk there either.
Gene and Hugo's review of the bookshelf and Marshall's on a 5.1 setup helped tip the scales for me when I was shopping. I concur pretty much across the board with their observations. They're clean, neutral and maintain very good composure at high volumes. They're not "power hungry", but they can handle plenty of it without bottoming out or breaking up. The tweeter is very nice. Good detail with no harshness or grain. They're not forward or bright, and easy to listen to. Great, detailed mid bass and they dig down to 30 Hz with real authority.