Well, Q3 was a play for a multi. Q4 went back to the story of Q2 and continued. Doesn't have multi. I revisit on a regular basis, so trust me on that.
UT is exactly it's name sake Unreal Tournament, a competition. Although you can go through a competition tree similar to Mortal Kombat, the multi-player application was equally strong. Some better than others. UT2004 (iirc) didn't have vehicles, but had a great number of maps and very flexible weaponry. Loved it.
Both have a good set of weapons, but UT had more to remain competitive in its variety of maps and game styles. Alt firing and combos were also focused on to enlarge the tactical choices rather than force players into a corner.