I had a supercat 17 for 4 years and it was an excellent boat. The one thing that I would look out for are indentions on the bottom of the boat caused by being on rollers. After about a year I had my left hull crack from the keel straight up to the front crossbar. The hull is not very thick at the seam on the bottom and it broke like a big toothpick while I was out on the wire. I repaired it and sailed it for several seasons. If you would like to see the repair I have lots of pictures...
I would also like to mention that the supercat17 sails the best with the bow low in the water. If the rear crossbeam hits excessively it's because the crew is far to aft.
The boat is a real pleasure to sail. I liked it so much I bought a supercat 19 brand new...