It sounds like perhaps you did not enjoy the sailing experience on the cat. Don't give up on them. The 420 is a very poor sailing cat. The 2000 rpm issue on the engines was also a bit strange. The standard yanmars in most cats should be in the 2500rpm range for cruise and propped to hit 2800 to 3200 at full throttle. It may well be the cooling systems need a major overhaul and they placarded them to avoid fixing the issue. Give a different model cat a try next time. You should notice a big improvement.
G