I have always been partial to J Boats, and would go with the J30 given those choices. It is true that two of those boats made it through the storm that wiped out the fastnet fleet, one of them singlehanded. Neither of the boats you mentioned are cruising boats in the traditional sense, but I am sure you already know that. The J 30 certainly can be cruised. For how long and with how many people really depends on your needs and wants more than the boat.
If you do decide to go with the J, one thing to watch for is a soggy bottom and transom. The diesel exhaust had a habit of leaking water into the core, and if not corrected early enough it would spread from the transom to the bottom. It is repairable, but at this point you should be able to find a boat that has already been corrected and is dry. Again, you may already know about this, but I feel I would be remiss in not pointing it out.