that depends entirely on what type of beaches you'll be hunting.
Fresh water only - Tesoro Tigershark is generally thought to be best next to the minelab excalibur which will beat it on depth, certainly the tesoro warranty and my experience with them is that they are excellent for this.
Salt water - the excalibur will give you the ability to discriminate, otherwise you could go with a PI if you don't care about that.
Both... I found the Detectorpro diver does very well on both for not too much money, otherwise again..the excalibur. I hear good things about the Fisher CZ20 as well.
My two cents - hope it helps.
