Well I guess I'll type this out again. I had this half page reply ready...and I guess I timed out on the forum and lost it all.
Frank, I hate to say it, but my experience is still very limited. I spent too much time working and not enough time sailing to offer anything with authority.
I do know it's taken me a half dozen tries to get the kinks (most of them) worked out on the Jen. The biggest problem has been with the furling. I don't know why, but it's much more difficult than the jib. Issues have been too much line on the drum, not enough line on the drum, tangling inside the drum. Furling by hand does not equate to furling under load where the sail is wound tighter and has more wraps.
Other issues have been having the sail get hung up. When I unfurl now, I have someone stand by the mast and help guide the sail around the wings and the trap lines. Any one of which have hung me up before. make sure your Jen sheet/ control lines are run well outside of the boat and all other lines or wires. Run them over the top and not under or in front of the forward wings.
I still have issues with the ratchet blocks, and haven't figured out the best angle for them.
Don't expect too much out the Jen. Does it help? Most definitely, is it the same as a Spin on a run? No it's not. However, I've used mine on a beam reach in light winds, and you can't do that with a spin.
Recently me and my brother in law entered the Hagar's Run race. It's just a fun 20 mile distance race and nothing serious. Anyway, we got spanked pretty good. It didn't help that 30 seconds into the race my jib halyard broke,
but that only delayed us a few minutes...well it broke again on the return leg too and I wasn't able to recover from that, but I digress...
The fastest boat in our group was a H16 with a raw time of 2hrs 50 minutes and my time was 3hrs 13 minutes. My goal really was just not to finish last! We did accomplish this and even finished in front of a Vector Wave 16 (don't ask me how)
Here's the real yardstick. The spinaker boats, F16's, Nacra 20's and even an H21SE had a 5 minute time penalty, and had to run another 12 miles. The fastest boat in that group had a raw time of 3 hrs 19 minutes. On the downward leg most of these boats blew by us. I thought it was pretty amazing actually.
I think we could have done a little better. Had the wind been out of the east as predicted, we could have flown the Jen on a beam reach all the way up and back. True all the other boats would have been faster as well, but the extra sail area of the Jen would have helped equalize things. As it was everyone else in the "light" boats were flying hulls, and we couldn't...unless I went over the the leeward side
The bottom line is the boat's heavy and so am I...
Frank, you can contact me if you wish, I think my address is listed, but to be honest I'm not the expert you're looking for!
Edit. I just re-read what I wrote above and need to put a qualifier in as far as the ease of furling the Jen vs. the Jib. In reality they're about the same...once the sail is furled right and there is ample line on the drum. My difficulties were in relationship to the PITA learning curve issues that kept popping up.