My father owns a
grampian 30, and I can say that the 30 is definitely not designed for
offshore. It has a huge
cockpit with poor drainage and is a very stiff
boat, huge windows, and is pretty stiff (which will be comfortable but not kindly if you're to get capsized -- it means you'll recover more slowly). The boat pounds a helluva lot when going into a heavy sea, and when running in a heavy sea tends to squat a lot so the stern digs into the
water.
The 34 is obviously a different boat, so take this with a grain of
salt. Just my thoughts on things to look at when looking at the 34.