The Quick and the Undead is, finally, the first movie to actually render its own storyline null and void. It is, essentially, one gigantic plot hole.
Aside from that, the acting was quite bad, character motivations nonexistent or unbelievable and there wasn't a single character worth hanging our hat on. The most interesting cast member (who had great potential to be a dark horse protagonist) got snuffed halfway through the proceedings.
What the Quick and the Undead DOES serve as is an excellent example of how to do good color-timing. It looked excellent, when you take into account budget considerations.
Unfortunately, it plays out like a guy got his hands on a hundred grand and watched a few westerns (most notably The Good, The Bad and The Ugly) and then just threw a bunch of elements haphazardly into a movie... "you know, they have movies where characters do THIS! Does it fit here? No, but who cares! They do it in other movies so I should do it here!"
Maybe a good view for burgeoning cinematographers and colorists (first-year film-schoolers). Otherwise, a must-miss.