Since it is harder to change headsails with a roller rig, I've found that
sail plan and size is more important than I've heard discussed.

My E32 came with big 150% Genoa on the theory that it would do everything.
The problem was that, when rolled up to the size appropriate for the typical
strong wind, it lost too much shape and had too much bulk rolled on the head
stay for the boat to go to windward well. I therefore had to carry a
working jib in case I was ever faced with a long beat to windward and go
through the whole swapping routine. Changing headsails on a roller rig is
harder not just because of the foil set up but because a "do everything"
roller Genoa has to be of heavier cloth to stand up to the strains when
reefed and the rolling. Add luff foam and leach sun cover and It makes for
a big bulky sail bag and hard work bagging on the foredeck.

I had my new headsail built last winter cut to 135% size with a very high
clew. The latter feature makes sailing in congested waters vastly more
enjoyable and safer at a performance penalty I would only notice in a race
with an identical boat. The area reduction means that the sail will still
have decent shape when reefed down to size for 20 - 25 knot winds. I really
haven't noticed any performance difference with the full sail plan that I
can tie to the reduction in overlap.

I no longer carry the working jib although I will put it back on board for
any long trips that might involved long beats in 25 knot plus winds. I used
to change jibs a couple times a month as different weather systems went
through but, no more.

The E32 is a bit on the tender side so these sizes are not a guide to all
boats. If you are ordering a new roller headsail, figure out the jib size
for winds in the low 20's and tell your sailmaker to make the full size such
that you will still have decent shape when rolled down that amount.

--
Roger Long