I agree with DonM's choices on beach detectors in that I prefer the "no longer made" Fisher CZ-6A. I have owned one in past years and I kicked myself in the butt after having been foolish enough to sell it. I am pleased to say that I was recently fortunate enough to be able to score a nice CZ-6A off of eBay.
You could also consider the more recent CZ-5... it's basically the same detector but not as water resistant as the CZ-6/6A series and it comes with a built in speaker for use without headphones.
On another note... there is an awful lot of Fisher Coin$trike's up for sale in the classifieds and on eBay at tremendously low prices. These digital ID detectors are Fisher's top of the line models and I am told that are comparable to the CZ units for beach hunting in the dry and wet sand.(Maybe BFL525 will respond here... if not, check out the posts in the Coin$trike forum for more data.)
In regard to the Minelab detectors for beach hunting... the Excalibur and Sovereign models are the ones that you read about the most on the forums, so I would have to say that they are top notch also.
Good Luck in your choice and Happy Hunting.