I think ULF is actually quite transportable but it depends on how how much you're willing to invest in the logistics of packing the beast around though. It is definately slower going. I place limits on how many film holders and lenses I can take (no problem---I only have two 12x20 holders anyway and both my lenses are close in focal length, differing only in contrast) The truly awkward part is the heavy tripod, but if I really want to get a shot on 12x20 I can almost always find a way to do it. Vittorio Sella took a ULF that shot glass plates to the top of the alps---certainly we can be at least as creative when it comes to problem solving!
For me anyway, problem solving is part of the fun of ULF.