hans,

In my experience, it is still better to have e-tickets. Paper tickets still need to be endorsed by UAL before you can use it on another airline (unless you have a full fare ticket), so it does not save you any time.

I also find that if I have an e-ticket, I can always call UAL and they can change it pretty easily (and quickly) over the phone. If not, when you arrive at the counter, then have to re-issue your paper ticket which could take a little longer.