nah, disregard that post. after more extensive gameplay and testing in training mode, i can confirm 3-button input failures. according to key display though, it seems to corroborate with what youthasia posted. i also readthat this input problem might be due to button sensitivity. according to key display, sometimes my 3 button inputs would register one or two buttons before the entire 3-button input, thus resulting in failed output.
another test i performed was turning on ultra and super meter and attempting to do ultras. most of the time with both bars, an ultra attempt turned out to be a super. however, without the super bar, ultra attempts always turned out as ultras. this seems to be further evidence of the uber button sensitivity of the stock parts.
i might try to swap out the buttons before messing with the PCB and see how it goes. sorry if i misled anyone with that post from earlier.