tubeless or tubes

The consensus around here seems to be that UST is a reliable no flat option as long as you put a little bit of sealant in case of a thorn. Not the lightest setup but for a 100 miler I'd give up a little weight for peace of mind.

I wouldn't feel comfortable running a stans conversion setup for 100 miler.

I have crossmax sl's but havn't run UST tubeless yet. I'm getting some ignitors though because I figure ~610grams for the tire plus ~40 grams of sealant isn't that much more than ~500gram tire plus standard ~150gram tube.

I love my tubeless...but there's always a chance for a sidewall slice or a hole that stan's wont fill. I always recommend you bring a pump or co2 with spare tubes, especially on a 100 miler

I run Stan's, and regular tires.
Not as reliable as UST, but a lot lighter.
From my experience, you are much less likely to be standing by the side of the trail with tire levers in your hand with Stan's than with tubes.
Nothing is fool proof, so I usual ride with a couple of spare tubes, and a pump. I've never needed both tubes, but you never know.
In a race, I carry a CO2, and 1 tube.

I have yet to have a flat with tubeless. I run a irc serac ust tires on bontrager race wheels w/ a bit of stans. With tubes i had flats veery week. Any little silly thorn would at the very least cause a slow leak. With tubeless and sans no problem. As long as you have decent pressure on the tire, to prevent burping, the tubeless is veyr very reliable.

I'm going to run UST on the rear again. Been using a tube and standard tire on my UST rim to save some bucks, but I'm going back. Never had a problem with mounting UST's using a floor pump. CO2 does the trick on the trail with my mini pump taking care of the rest.

My bike comes in at 23.3lbs with Olympic ZTR tubeless rims and Maxxix Ignitor 1.95 UST (and put Stans liquid in them). I will never go back to tubes. As someone mentioned above...for a 100 miler take a c02 and an extra tube incase you slice the sidewall.

Tubeless for sure.
I use non-tubeless tires on UST rims with Stan's juice. It allows me to use regular tires, which are lighter than tubeless tires.

Tubeless is the only way to go. Run a bit of Stan's in them and your pretty much worry free. The weight issue is so minor versus the time lost changing a tube. If you are looking for light ust check out Hutchinson scorpion lights for rougher terrain or Michelin xcr2 for dry hardpacked.

http://matthewspak.blogspot.com/

I'm running Stan's (w/ non-ust tires) and love the lower psi grip. So long as you put more Stan's in every 3 or so months you should be just fine. In the event that I get a flat (so far only have when I cut a tire) I carry a tube and co2