Just to note my personal experience with Ulocks. I had always bought the best Kryptonite locks I could get when I purchased a bike ($1000 and over GT's with a cable lock? yeah). Anyway, last year at the LB GranPrix, I locked the bike up w/ a Kryptonite Ulock (combination kind - no keys involved).. Anyway, the combination mechanism crapped out and when I tried to leave, the lock wouldn't budge. So after much physical violence directed at the lock, I gave up and called a locksmith.
Suffice to say that all you need is a cordless endgrinder with a decent cutting wheel and the >priciest< Ulock will literally cut like butter. Keep that in mind when you're locking your nice bike up...
.. or perhaps when you're looking for a new bike >🙂