Thank you all for the comments:

There are no Isotope in my area and I have never seen one in my life. I might consider one if it became available as long as the rigging is in good condition and the parts are reasonnably available. For that boat, I would have to sail it before purchasing it.

My area of search is Quebec, Montreal, Toronto, New England. I might drive down to Cap Hatteras next year so the I95 down to Richmond would be included in my search.

I really like the Nacra 5.2 because it is a Nacra and I feel that I would get accustomed very fast on that boat. Also it seems faster than my Nacra 5.7 unless it is really blowing hard.
I am certain that the boards will help alot to right the boat after a capsize.
I will also look for a Hobie17 even if it rates slower than my Nacra 5.7. I am willing to take a performance hit for the conveniance of a more manageable cat.

I often sail my boat solo but one capsize, it is very difficult to right, in fact it is almost impossible and if I succeed, I would be exhausted and my sailing would be over for the day. My new lake is not a sailing lake and I often find myself being the only boat on the water. Most of the lake cannot be monitored from the club so that is why i want to change boat.

As for the Prindle 16, I sailed it very often a few years back and I loved it in strong wind, but I would really prefer a cat with boards to improve the upwind ability. Also, my current Nacra 5.7 is much faster than the Prindle16