All sea kayaks are good boats. You have to find one built in a style you like, feels good in the conditions you will be paddling in, and fits you.
The number one priority is an adjustable skeg. The Cape Horn has a rudder, and I have yet to put it in the water. A skeg works as well with fewer parts and a cleaner looking boat. The only disadvantage is storage room taken up by the trunk in the aft compartment.
It should have recessed deck fittings, 3 bulkheads, day hatch and good size bow and stern hatches, perimeter deck lines, lots of bungie cords, at least 16' long, under 24" wide, good initial stability, great secondary stability, and a good physical fit.
Besides another Tempest 170, my list of potential boats includes:
Current Designs Sirocco
P&H Capella 166 RM
Necky Chatham 16