I sail an old 5.2 and I love it. I sail it solo 90% of the time and it is great to sail that way.

When the wind really picks up I don't use the jib and still can solo easily.
Also I can right it solo at 6 foot tall and 180lbs. I don't think I would go much larger than the 5.2 for solo sailing.

Once you go cat you never go back! Nacra 5.2 (Elsies)#1499, running an inter17 spin!