Well, Jimmyfreewall I personally like to see a counter of the number of testimonials a product has, it means people is writing REAL testimonials. If you choose just 3 it may look that you invented them in someway. But you should have all in some kind of archive page. Good luck with it
People already have short attention spans and the biggest mistake I see people make when trying to sell a product is an overwhelming sales page and too long of a video. Today on another foum I saw someone include all 38 (or was it 48?) testimonials and it was a complete turnoff. Less is more. I wouldn't include more than 5. If you include too many, it looks somewhat unbelievable (to me).