I think the UL is awesome. I have not owned one or shot one, so I can't speak from experience. I sure like it, I'd love to have one too!

That said, I think you really only gain a little over the MK. A little less weight for sure, plus what Mike said...the more closed breech area. I doubt you gain anything in your shooting, they both shoot great and my guess is your load(s) would likely be about the same. For about $600 difference in price over your mk... I guess you have to weigh the pros and cons.

Of course, it would be nice to have both