Well, I didn't realize there was a thread going on about my jib! Thanks for the compliments, Greg.
So, I bought the jib used from Masthead Sailing Gear -
http://www.mastheadsailinggear.com They have a bunch of cheap, used jibs that could be candidates for our boats. According to them, the jib is from a "US 2.4 Meter" boat. It was made by North Sails and is 4oz dacron. I believe it is around 35 square feet. I can measure the dimensions if anybody is interested.
As Vetgam confirmed, the jib definitely adds speed to the boat. After unfurling the sail and setting the jib sheet, I can feel the boat get a bit of a speed boost. When the jib is out in the right winds, the boat definitely moves faster than what I'm used to.
There seems to be a sweet spot, around 5 to 10 mph winds, where the effect of the jib is felt the most. Below this range, lee helm is very bad (which I expected) and I have to over correct the rudder to keep the boat on course, which slows the boat way down. The lee helm also makes it hard to get the boat pointed towards the wind and windward sailing is pretty much impossible with the jib. Using the mirage drive to "motor sail" in these light winds, helps bring balance back to the helm and the jib starts to provide a bit of boost. Once the winds get to about 5-7mph, the drive is no longer needed and the boat starts sailing, although lee helm is still bad. In this mode, I'll pretty much sit out on the haka up by the mast and out above the front aka bar to help balance the helm. This is one of the best views, watching the jib work, and watching the hulls pierce through the calm water. Once the winds pick up to about 7-10mph, the helm balances out and I'll move back to the center of the boat over the rear aka. This is where the effect of the jib is felt the most. Around 12mph I feel that the boat is being over powered and I'll furl the jib.
I'm still working on my furling system. At first, I had the jib furling around a pvc mast, which worked great, but the weight of the pvc killed the jib shape. I then ditched the pvc and just used some low stretch line along the luff of the jib. The jib shape improved greatly but unfurling the jib was not smooth at all. I then replaced the low stretch line with some tubing that I had laying around that is used for the water supply line for refrigerator ice makers. This improved the unfurling of the sail but it still doesn't work as great as I'd like. My next attempt will be to try some 1/2" pex tubing.
I'd love to snuff the jib and ditch all of the furling stuff, but the dacron definitely doesn't seem snuff friendly.