There are very few UST 29er tires out there, for a reason. They'd be heavy and just wouldn't sell. Manufacturers are increasingly slapping the "tubeless ready" label on their 29er tires, even those without a UST bead, blurring the line between tubed and tubeless ready. twentynineinches.com has had some great articles on this topic, here's a sample:
http://twentynineinches.com/2009/04/28/do-29er-riders-really-need-ust-tires/Personally, I am currently in the process of losing my mistrust of converting tires intended for use with tubes (e.g. using stans rims). I've been using TLR on 26" UST rims with Stans sealant with great success for several years, but I just recently entered the 29er world when I got a Fargo. I quickly upgraded the wheels to a Stans wheelset, and then got stymied by the lack of TLR 29er tires with UST beads, a system I had learned to trust. Eventually I decided "what the hey" and converted the Vulpines that came with the bike. It was quite easy and they held air great, and I got all the tubeless benefits - nice and light, with a supple ride.
I grew less enthusiastic when I got my first puncture though. The Stans ran out without sealing the leak. It took a good 30 seconds to all run out, and I kept shaking and made sure the puncture was at the bottom, but no luck, all I got was a puddle of sealant. This was new to me, my 26" TLR tires always sealed without a problem. My theory is the Vulpine carcass is just too thin for the sealant to find a purchase and congeal.
So now I'm back in the same position you are in - looking for that ideal 29er tubeless solution. I figure I'll try converting something a little beefier next, like a Maxxis Aspen or the Conti Race King. Hopefully these will seal better when they puncture.
