I don't like the Blaster for PCE or MD. The d-pad is stiff and not circular. I'd put up with the narrow shape of the pad if there was a reason to use a 3-button pad, but I haven't encountered one yet.
Yeah, that sounds like good info to share with folks before they buy something. So...
I should make a disclaimer: I love Famicom/NES controllers in general (including the d-pads)...
...and my Ave 3 (in addition to the 3-button Blaster above) are my “go-to” pads 90% of the time.
I have fun using the third button to shift speeds in shootemups and other random functions in a handful of games.
3-button pads, in general, are not necessary, but I happen to love using them (only a small percentage of games utilize SELECT and/or RUN button in a significant manner...so clearly, I am easily entertained).
WARNING: The 3-button PC BLASTER has a switch that might be annoying (sharp and pokey) depending on how you hold the controller. My kids don’t like it, for example, but I don’t have any issues.