I'd say it depends on your application. Are you wanting to competitively track/autocross the car? If not, then I see nothing wrong with a UPR piece for mild street car/occasional autocross usage.
A "deal" on a used UPR front end kit vs a "new" MM front end kit I imagine is quite substantial in the $$$$$ dept.
Whooaaa!! I certainly retract my statement. I must have had a different K-member design in my head when I grouped it with "UPR".