I would not recommend under any circumstances to do ubers alone. I planned to save up enough keys to do three torch runs, so if I managed to get two friends to help, their efforts wouldn't be just "thanks, cya!"
Uber Diablo I could kill in under 10 minutes with my frenzy Barbarian because I've snagged a few games where 17,000 SoJs were sold and wound up with him replacing a super unique. I have no idea about the other two, but try your best to face them one at a time.
On the other hand, Lilith was quite a surprise. Couldn't land two hits on her without dying from poison. And Duriel's minions were a pain for the same thing.
I can has sig nao? Plz?