While I’m a huge fan of the B’stone YHC, in many ways the MG yellow is a better tire. It is a bit faster for it has better grip. It doesn’t fall off with heat cycles like the YHC and it seems to last a bit longer. You should be able to get 2 race weekends out of it with good tire management and unlike the YHC which would be noticably slower the second weekend, the MG will be close.
MG Yellows puts you in line with Tag USA of approved tires so your driving style and setup information will be helpful if you leave the area.
But remember, new tires are always faster than old tires.