C'mon!! I was right about something for once!
I think the 21E/ Extreme is a great looking boat, I'd expect a fair difference in sea handling ability. Is the 7ft beam version a deeper 'V' than the 6 ft beam, else i'd expect the narrower boat to cut through the wake better?
As for the speed, is the 21E and lighter/heavier than the 21C? I'd imagine that in an average chop over here a novice (as most of us young'uns are!) could keep a higher speed in the 21E thanks to the extra stability, yet I'd expect the 21C to be lighter and therefore faster in the flat?
Thats quite enough thinking for me at this time of day!