Right now I've got a 5/8 cable and a master lock combination lock. I like the combination lock because this one I can program to the same combination as the lock I use on my locker. That way I only have to remember one combination and I don't have to carry a key.
The lock its self doesn't seem too secure. I think master locks these days are made pretty cheap.
I've been looking at the round bar, solid steel type locks. I wonder if they're any more secure? I would be really limiting myself to what I can lock the bike too.
What are your thoughts?