Fast and tricky to sail well. The outboard model will serve you well, inboard will slow you down. I sailed its little sibling the Capri 25 for a couple years. These boats are better than they lead on. Obvious takeaway are, sail it as flat as you can depower main first, sail with a bubble upwind as things pick up. The Capri 30 came in Fractional 7/8 and masthead (more common), they also came with wing and fin keels, but most common was fin. Backstay defines headstay sag (less then bend), you can power-up with sag, and harden up to point. As with most of the Capri line the bulkheads are usually the weak points. The mast step is also a problem on these look for soggy under it, and soft. What you don't want to have is backstay is pushing the mast through the bottom of the boat.
These boats are light air machines. Hate waves. You have to become a master at dodging waves in any kind of seas. When things get extra-light, they start to shine. The huge kite makes the boat a log of fun downwind, and usually passes everything even over 35 feet. DDW is your killer point of sail (kite up). Boat gets squirrley downwind as things hit hull speed and you surf, you get weird pockets of no bite no the rudder. Balance crew to keep you steering.
The Capri 25 liked 10 degrees of heel or less. The Capri 30 didn't spend enough time on to know but I bet its the same.
I felt that the Capris were severely under appreciated boats.
Someone got crazy and outfitted one with a taller carbon rig and a blade keel with bulb, said it was a rocket.
If you get REAL ambitious, I have nothing but great thins to say about epsails.com for these boats. Below is us under kite on the 25. She presents a LOT of sail area downwind.
I know these boats pretty well. As noted the Capri 25's remain really good PHRF boats, easily sailing to their ratings in light air. Less so in a stiff breeze (unless there is a longish downwind leg) or in a chop. The 25's were really underated. But the same is not true of the 30's. They were much less competitive under PHRF. If you are really planning to race, for the dollar you would be way ahead of the game if you can find a well maintained J-29. They are much more consistent performers under PHRF under all conditions. Another great option would be the Kirby 30, if you can find one that has been converted to a masthead rig. That said, the Kirby 30's took a little more skill to sail to their ratings. Lastly, S2 9.1's do extremely well under PHRF, but you need to have a comprehensive survey since they are extremely prone to core issues. (Even more than the J-29).
I know where there is a nice 9.1 for sale in virginia (no I am not selling it, and it is not mine, or even a friends. I have looked at it in person though and it was a consideration for me to purchase back in the Fall). Its nicely maintained. No trailer though. I bought my boat from the broker back in Oct, is only reason I know it exists. I am frankly shocked it hasn't sold yet.
View full details & pictures of a S2 9.1 located in UNION HALL, Virginia with pictures & full details of this Cruiser/Racer built in 1984 and available for sale.
PS: I defer to Jeff's experience with the Capri 30. I only sailed on one a couple of times and it felt very much like my Capri 25 to me, only bigger. I did not race one, or against one (except as a kid).