I've always found Spaz faster to use in the default SP levels. I swear he can literally skip some parts of the levels. Jazz/Lori only has like...one area that they can only reach with copter ears IIRC, which is a c/1up/notsureexactly in one of the last levels. gg. When it comes to actual challenging custom SP projects, that's another story... copter ears can really save you from dying/getting hurt in SP. I haven't seen witches used much, and it's easy to skip the one used in the shareware episode. Just run to the right.