Some advise Hobie 20 1990 or Mystere 6.0 XL

It depends on where you are sailing. If you can leave it setup I would go for the XL. If you have to set it up every time it can be a bit much. For the ocean I would take the mystere any day. Construction is about the same quality. I have seen problems with both boats.

Thanks Jeff,

What problems have you seen on the Hobie ?

Many of the first boats had hull problems. It is a shoe box build(hull sides are being supported by the deck lid). Where the newer designs (including the mystere) are built in vacume bagged halves and deck lids. This gives a stronger build since the top corners are part of the structure of the sides. The problem with the H20 is that it eats crew's body parts. The jib cars on the hull are right where the crew comes in off the wire. The mast rotator on the tramp is always in the way.
The mystere has rudder problems. The rudder build is bad and the kick up system is worse. Many owners went to other manufactures rudders and castings.
The mystere mast is all aluminum and light enough where it is easy to step. The Hobie has a comp tip which can lead to problems if you hope to run a spin.
The later mysteres are much better. They started using epoxy and went to a larger diameter cross bars with intergrated traveler tracks. Not sure about the 99.
Both boats are orphans and may be hard to get parts for in the future.
I know there is a strong Mystere presence in Montreal and you should not have any problems getting together with owners in your area for more information.

ARC21 has none of those issues, self tacking jib, beautiful rudder system, tons of reserve bow volume.

But the mast is a beast. I would put an ARC rudder system on my boat in a heart beat if I could afford it.

The mast is a bit much, I built a gin pole and now raise and lower the mast single handed.