Considering the vintage I'm pretty sure the ASCII stick for PCE (if there is only one, not sure) is probably not that great. Their sticks for SNES and Genesis weren't very impressive, so I doubt a PCE one would be either. The first good sticks I used from ACSII were from the DC era, and even then that was a sort of high point. I just bought a used PS2 so I could play newer fighting games and the only stick I have for it is the blue and black ASCII one with the octagonal hole in it. Its better than a Dual Shock 2, but it still sucks. It is, however, way better than the DC ones with optical sticks in them (round hole) those things were just garbage.
For PCE, unless you can find a Sigma stick (unlikely) you are better off with something home made, or hacking a Hori Real Arcade Pro.
As for the mouse, its not that well supported. The most popular game that works with it is probably Tokimeki Memorial, but I prefer to play it with a normal controller. Same goes for the Saturn version. The one game that I'd like a mouse for is Nemurenu Yoru No Chiisana Ohanashi, and chances are you don't give a crap about that game since I'm its only fan over the age of eight.
You can see the mouse logo in the upper left there...