well for one there seams to be massive amounts of "ambient lighting in the udk scene while in maya everything that isnt facing the camera is BLACK meaning there is no ambient light at all.
Holy moly, can you show us the wireframe? This is nuts, by your posting time I'd assume a 4+ months project. Such an insane amount of blood in this thread
Your stuff looks like it could be pretty good... but the JPEG compression it really hurting your presentation. Re-save your shots with a lower compression amount.
I am making it with a decent amount of details but I keep having this weird idea that I should stop and actualy start getting the final texture touches.
Lower one is better for baking. More or less. But should also take the same amount of time. Also your UVs suck. That curved thing should be straightened.