You've summed up the Quasar 50 exactly in your 2nd sentance!
I've only been on one for a daytrip (Kuralu in the BVI) I talked for quite a while to the English owner and discovered he'd sailed a lot of the world before ending up in the BVI. They are great, solid seaworthy boats but.. They don't have anywhere near the space of a modern 40 - 45 foot boat.
That's about the extent of my knowledge I'm afraid. You might do better asking on the Prout Owners Association
PROUT OWNERS ASSOCIATION
There's a test of a Quasar from back in 99 by Charles E Kanter (who knows a thing or two about boats) here...
http://www.michaelbriant.com/specifications.htm