Not as in the wrinkles in my sail! I do still have a few of those but hardly any. I have just come in from the perfect daysail, 12 - 15 knots of wind, clear skies and a smooth, sparkling blue sea, and I do believe that I have finally tamed my sail. I believe I can now reef or furl it in the dark. The Paul Fay style of standing luff parrels have transformed the way the battens stack - I now have positive batten stagger when reefing or furling. I still need the long fixed batten parrels as well, or the sail hangs too far away from the mast and puts too much load on the Paul Fay parrels. There is a little bit of extra friction when hoisting - no problems when lowering - but that is easily overcome by using the winch handle to hoist the last two panels. In the past I was able to sweat it up by hand with just one turn of the halyard around the winch. It is a small price to pay.
The other two developments that have been vital to taming the sail are the Arne style of throat hauling parrel that transforms the way the sail sets, and the Paul Fay style of yard hauling parrel which works in tandem with the throat hauling parrel to peak up the yard.
I have also refitted my HK parrels. They are no longer needed to control the diagonal creases in the sail - they are almost slack when the throat hauling parrel is set up - but they do help a great deal to stabilize the sail when hoisting and lowering in a swell. The HK parrels go slack of course as each panel is furled but the panels above retain their relationship, an important issue for my HK sail which has 1.22m between battens in the lower 4 panels. And I proved to my satisfaction today that they do not detract from windward performance at all (neither does the mast). Arion was going like a freight train on both tacks.
Now that I have confidence that I can handle my sail in all conditions, particularly in minimal visibility, I can see no reason why I would revert to a flat sail. On the other hand, if I only had a flat sail and was fully committed to long distance voyaging, with little coastal sailing planned, I would not bother upgrading. (I have a few friends who sail this way, spending long periods in particular ports before making another bluewater passage. I have always done a bit of both.)