Should I buy a Kiev 88?

I have a K60 for many years. It is solid made and a work horse. 13 images per film are possible.

I was originally interested in the kiev 60, but then an 88 showed up, and I bought it. what about the 60 makes the 13 images per roll possible? I imagine this would be possible with the 88 too, seeing as they're both designed for the slightly thicker soviet film stock, right? my back does indeed underadvance the film just a bit. where does the film actually start under the paper (where do you set up the first frame)?

> what about the 60 makes the 13 images per roll possible?

The negatives are closer by each other.

sorry, yes, it doesn't have anything to do with the film thickness.