I had a 1983/4 Force 4 GT - 50HP Suzuki
The hull was a very shallow V - its almost flat at the bow. When I stepped up to a 4.7 Tornado, which wasn't hugely bigger, distances which seemed like major trips in the Force 4 became insignificant in the Tornado.
The boat was good fun though - very nimble and pretty fast.
The biggest design flaw IMHO was the transom, they weren't all that strong. I've seen many reinforced. The deck bolts for the stainless transom supports kept getting pulled through the deck on mine.
In summary - great boat for its time, but RIB design has moved on. If you are really after a 'seaworthy' (long distance/rough water) boat I'd keep looking.