This resolution 'enhancement' sounds suspiciously like the 'motion enhancement' that manufacturers use to 'improve' motion by interpolating artificial intermediary frames between the actual frames of a source.
So, what I'll say to that is some people like this sort of enhancement and some don't. I fall on the side of the argument that I don't want my display adding anything that wasn't there to begin with. Now, we're getting into a sort of grey area here as, unless the UHD set just quadruples every pixel of the 1080p source, it HAS to scale the source up similar to how an HD set HAS to scale an SD image up to fit the pixel count of the display.
In either case this isn't an ideal. I'll tell you that DVD looks better played natively on our 56" CRT RPTV than it does upscaled to any of our digital (DLP, LCD, plasma) displays. Having to create something from nothing is always going to leave a lot to be desired.