It looks like I'm going to have to buy the Monoprice branded tool because although the locking mechanism is the standard one, the width is too wide, as a guest reviewer stated in 2014. It seems Monoprice has not taken this into account. Therefore if you have a standard punch down like the green one from Home Depot, you can't use this blade.
I really can't give a review of these blades because I'm still using the original blade that came with the punchdown tool. I'm sure that if they are anything like the original, I won't be ordering replacement blades until about a year from now. Sorry Monoprice!
PROS: Nice sharp cutting edges, easy to change out!
CONS: None found in the month or so that I have owned them.