From an earlier post the OP had

>>Hi. My name is Manuel, and I am building a project around the PIC16F628A and a piezo

http://www.picbasic.co.uk/forum/showthread.php?t=5773

I, in a sloppy manner, left the A off of my reply about the 16F628 datasheet. I had checked the 16F628A sheet and saw no clamp and was just reporting that observation.

However with an actual look at the 16F628 datasheet and the others noted, I see why Darrel asked

>> Which one are we supposed to believe

Great question by Darrel ... here is my version for an answer - if it were a one-off by a school boy intending to rudely disrupt the class room I would go with the 9V on RA4. If it were for a medical device or other lawyer-attacting application, I would go the NPN route and would want a written response from Microchip as an effort to help keep by butt out of court should there ever be a problem before going the non NPN route.