First a few details about myself:
I am 29 years old, almost 30 and am an incoming graduate student to UC Berkeley for nuclear engineering. I have taken math courses up to multi-variable calculus and will most certainly continue.
Before the adjustments to math mastery, I would utilize the mastery system as a way to quiz myself and review grade school math and see what areas I needed to brush up on. Now with the time limit adjustments I find myself running out of mastery time before I find any subjects that I feel need my attention. After mastery is on cool-down the amount of time required to find problem areas is considerably lengthened when I have to approach each subject individually. Theoretically, since I no longer devote a large portion of my time to grade school math "homework", I could forget mastery subjects just as fast as I learn them, negating the purpose of attempting to utilize Khan Academy as a math review tool.
My request would be for a flash quiz of multiple concepts, not for the purposes of learning but instead for the purpose of review, similar to what the World of Math was before the mastery changes but perhaps without the credit associated with grade school curriculum. (I'm guessing the mastery system needed changing cause too many youngsters were breezing through it and forgetting concepts in their schools.)