From experience, a pretty dry ride and copes with most sea states well. At 7.5 this should be significantly better than my 6.0m, which was a world apart from my previous 5.5m of the same stable.
They were well made but I am not sure how you will find the Nautiquew layout suits you for dive kit. The front sundeck and rear seat arrangement do take up a lot of space. Mine is the HD version ( ie, cheaper stripped down version, no teak decking and only the two man side-by side helming seat - great dry storage and best used in the leaning post arrangement) I have a fold-down bottle rack arrangement for 4 cylinders as part of the seat frame which works well.
The things to watch out for are poor wiring (auto electrical stuff - best ripped out and start again if not already done), water in the hull from poor sealing of the ducts, and on the nautique, check under the rear seat for water not running into the sump/bilge pump working and man enough) Quite a heavy lay up in that era and needs plenty of power
All JMHO and obviously you have seen them/it and assume you are happy the layout will suit your needs. Have a good poke around and a test run