Hello,
I don't know much about CIJ guitars, so I can't help answer that question.
As for the general question about frets, the answer might sound obvious, but the best explanation is to say that 'vintage' sized frets are smaller and lower than these medium-jumbo jobs. As for the difference in 'sound', I strongly doubt there is one. The difference is entirely in feel and playability, and it's completely a matter of personal taste. I own guitars that have both styles. My 51 seems to have pretty huge frets, my Tele has small frets, and my Jagmaster seems to be somewhere in between. My preference is definitely for the smaller frets on the tele. Maybe it's a hand strength or heavy handed or light touch issue, I don't know, I just know what I prefer.
As for what you would like better, I could not possibly answer that, and will not even try. I would say no one else on the site will try to answer it either.
