I beat the ROM of Rockman and Forte ages ago with both characters (I believe), and I didn't find anything about that game very challenging...
But it's kind of irritating: Bass is better than Megaman in almost every espect in that game. Sure, he may not have a charge shot and can't shoot while he runs, but he has rapid-fire...and the dash...There was no balance between characters.
Oh, and Culex isn't from any Final Fantasy game. (I was wrong. So sue me.) In fact, Culex's opening speech was supposed to openly mock the FF series' drama and such.
(And they deserve to be mocked, especially by Nintendo...Putting "Here lies Link" on the tombstone in the Japanese FF1...Bastards...)