John,
I have a 2 year old 420 w/ in mast furling. Like Greg, I am not sure how much less mainsail area the roller furling has v. the conventional main (you can call a Hunter dealer and they can give you the answer), however.... if you really want the full roach main, I believe Hunter is (now) offering a roller boom furling (full roach, full batten). And, it is possible to have an in-mast roller furling main constructed with full roach and full vertical battens. The convience of the roller furling main is wonderful, and not having to fool w/ traditional reefing, sail cover, etc. is (for me) well worth any small performance reduction. Would the extra expense of roller boom, or a new vertical batten main be worth it ??? Well,if you think about it, the only time it makes any real difference is up-wind in conditions between 10 & 20kts of wind. Over this, you are reefing either main, and under 10 kts of wind you are likely motoring to get somewhere. Off shore the main is usually reefed. Off the wind, there is even less of a performance difference. 420's are cruising boats... Whether you're cruising for a weekend, or a week, or a year.... you're generally trying to get to a specific destination..... About 1/3 of the time the wind is on the nose or too light to sail and you are motoring. About 1/3 of the time you are sailing (or motorsailing) downwind. So, only maybe 1/3 of your time underway will you actually be sailing upwind in conditions where the type of main will make any difference.... and then, probable not more than a few tenths to a half a knot.... There will be a thousand other things that you will consider far more important than those few tenths of a knot......... Now, if ya wanna race, well, that's another thing... but you're looking at a 420, which means your're looking at one of the most comfortable all around cruising boats out there.... you'll love it....
