Long Distance Competition/Ultracycling, Randonneuring and Endurance Cycling - tubeless tires?

i've heard good things and bad things about them. anybody had any experience with them, good or bad? i'm considering spending the extra couple bucks on them if they're worth it. i'm mostly commuting through the city nowadays, but offroad from time to time and i'm planning a long distance trip for the summer. any input would be appreciated.

Utterly pointless on the road.

If you get tyre damage, you are scuppered. No real advantages at all, except for offroaders running tyres at very low pressures.

YMMV

Not appropriate for road and especially long distance, randonneuring, ultras, where reliability trumps other claimed advantages.

Anyway, I just watched a mountain biking colleague spend big bucks and endless hours -- in the shop as well as stranded on the hill -- trying to get the tubeless thing to work. He finally gave up and installed some proper tubes.

Consider that they are impossible to inflate without a (fairly large ie 110vac) motorized
pump, and how often little cuts appear in the tread, which occasionally penetrate the
carcass and you will realize what idiocy these things are for the average rider (anyone
below the top 0.1% of athletic prowess). On a recent ride, an early adopter had to
call for a pickup when both of his tubeless road tires went flat. This was a 17mph
average pace 60mile ride.

I like the question in Bicycling magazine: "Do we really need a third way to attach tires to wheels?"

I can't see any benefit for using tubeless on the road, but I can imagine the difficulty of fixing a sidewall cut in a tubeless tire at 3am in the rain and the dark vs. sticking a folded up Snickers wrapper over the cut and replacing a tube.

well mountain biking if your worried about that then you would carry a extra tube anyways just in case. my buddie does. he hasnt had a flat and he has been running it for over a year now. i know a few guys that carry spare tubes just in case of a cut in the tire. at least then you can boot the tire like you normally would. i like the tried and true. i did think of going tubless for off road, instead i stuck with liners and normal tubes.

i have had some tire failures on the road and you just might catch me dead on the side of the road if i tried tubeless on my road bike. if im doing 40+ mph i really dont want to worry if my rear tire is going to explode prematurely from a minor slice that would never give with a normal tube.