I own both styles of UltraStingers (reflectors); one has a more SureFire like beam, and the other gives a tighter spot. I like them both, of course.
I also own several Magchargers, and I have to say that with the new Magcharger lamp, the Magcharger is able to produce a much tighter and longer reaching beam than either of my US's; and to my eyes, the Magcharger does appear to produce more light than the US. But the MC is a much bigger and heavier light than the US; so it's a trade-off.
I also believe the MC would stand up to more abuse than the US. This is a totally subjective opinion, based mostly on abuse other Maglights have been subjected to; So far I haven't had to hit a charging Rottweiler with my US, but when I did that, repeatedly, with all my strength with a 3 D cell Maglight, the dog was unable to continue the attack, and fled. I was *very* impressed with the strength of the 3 D cell Maglight, which is virtually identical in construction to the Magcharger. I sincerely doubt that the US would have held up as well.
That being said, I actually *use* my US's, much more than my MC's, due to their much more manageable size and weight.
The upgraded lamp for the MC is a significant improvement over the older lamp, and well worth the price, but a MC is still a big, heavy flashlight. It's a real work horse, where the US is more suited to general, everyday use, but perhaps, less abuse.
If I was faced with buying one or the other, I'd pick the US, for it's superior beam, (for shorter or medium distances, of course) smaller size, and much lighter weight.
If I knew the light was going to some rough use, I'd buy the MC.
One other point is that you can carry an extra lamp in the tailcap of the MC; the US cannot carry an extra lamp, and this adds to the MC's ability to operate under hard useage conditions.
HTH