That's where we stayed. The street it is on is quiet, but the other streets are not. Make sure you get a room at the back. It is quiet, you don't get the sounds from any evening entertainment and you get the evening sun.
The beach there is tiny, horrible and overcrowded - don't bother.
The rooms are spacious and the food was lovely.
Tip: don't go down to dinner too late or you will miss the desserts which are wonderful. They are set out on a first come first served basis.
Oh, and take plenty of insect repellent. The mosquitoes round the pool are vicious if you are a mosquito magnet. OH ended up having to get some antibiotic cream from the pharmacy, and we saw plenty of hotel guests covered in pink splotches.
The walk into town from the hotel is not a pleasant one so we used the train. You buy a ticket at the station and then have to validate it in the machine on the platform before getting on the train.
For the boat trip it is much cheaper to go down to the harbour and buy tickets there. The organised trips were 37 euros each and tickets from the harbour were 24 euros each.
I would also suggest that you have a guide for going round Pompeii, whether you get there under your own steam or go on an organised trip. You learn so much more from having a guide.