Perhaps it's a result of living in northern California, but I cannot see spending more than $1000 (x2) and 15 hours of travel time (x2) to see coastal towns. I am a self-confessed naysayer on the CT for the following reasons. Even if I cared about beach time, I'd have to say that the beaches aren't so great. Maybe, 20 years ago, they were quaint, "undiscovered" villages. Not so any more. During tourist season, they are unbelievably crowded; think of being jammed in, body-to-body, on a train between towns. They have relatively poor tourism infrastructure. I believe that the current craze for visiting the CT has exacerbated the tendency one finds in some sectors of the Italian tourism industry to treat travelers badly. If the weather is bad, there is NOTHING to do.
In my opinion, the AC is not only more beautiful, it doesn't suffer from the aforementioned defects. There are plenty of real hotels and B&B's (as opposed to private rooms) which operate in a business-like way, taking cc's, for example. There are good transportation connections to many major attractions; the towns, themselves, Sorrento, Pompeii, Capri, Paestum, etc. Finally, if the weather is bad, there are some interesting diversions such as villas, churches, and museums, which can be visited.