V7 with full epic pad equals which ski stability-wise

This may sound like a silly question. Let's say you put a full 4 layer Epic seat pad in a V7. 1.5 inches. Is there a way to gauge the overall stability of that combo against another a slimmer boat without a pad.
I am considering an upgrade but the market is scarce and I won't be able to test paddle many boats. So any rough idea would be welcome.

I could certainly feel less stability but did well overall. It was a reasonable and productive challenge. Still was able to put full power down in side chop and was probably even a tad faster than usual. No swimming and pretty occasional bracing.

I hope I am posing my question clearly enough.

tcsurfski.com/product/epic-seat-pad-set-4/

Thanks to Nick at TC surfski (and ?Wesley Echols who made up chart?)
..check out the chart-I wouldn't treat it as gospel though
I just noticed V7 not on there, but you can extrapolate.

Oh that's really nice. Looks like it would put me in a 2g V10 territory. Sweet.
Thanks again.