In a sailing squadron not too far from me there sits the beach-cat of my dreams: a G-Force 21 Grand Prix (21' long x 12' wide with a 33' mast). It hasn't moved in a while and I hear the owner bought a powerboat and hasn't done much sailing since. It's a beautiful boat in great condition and the last time I saw it out it had fairly new sails (Square-top and roller-furling jib, the spinnaker wasn't mounted that day).
My 5.7M is a lot of fun and just about ideal for me, but I'll need to buy new sails very soon (my sails are over 20 years old!) and I'd like to rig a spinnaker or screacher for all the light-air conditions we have in the summer. I am thinking I could probably buy the GF-21GP for as much, or less, than the cost off a new suit of sails for my current boat (if the owner can be convinced to sell it). I can leave my boat mast-up on the beach and just cat-trac it to the water, so the super-wide beam isn't an issue.
The big question, of course, is how much to offer for it?
It would be really sweet to keep pace with Tornados, and maybe even show them my sterns once in a while 
You might want to contact Hans, he designed and built it.
This link is to the G-Cat Forum
http:/
Have you ever sailed one? I have and it is a beast! I don't know how much crew weight you sail with, but in anything other than very light wind....it will get you attention.
Good luck,
Dave
I mostly sail solo (145lbs), and in the summers here we have a ton of extremely light wind, especially 11am-1pm. It's bad enough that I hit the beach at 11am, go get lunch, and go back out on the water around 1pm (sounds rough, I know).
When I have crew, I try to keep her in the 100-130 pound range (each) 
If I get this boat, I'll probably add another trapeze that runs through the mast-beam. Three under-150 pound people out on the wire each working a single sail could be pretty effective.