Grumpy..
I agree you need more than 1 detector if you are Serious about Metal Detecting..I hunt both Salt and Fresh Water and 1 machine would never work for me.You have one of the best machines out there,the Excalibur,for water and beach.I think a PI machine is a Must for Water and Shore,the depth from a good PI will out perform any land detector..I use a Minelab Sovereign for beach and sometimes the odd park,,it's pretty well the same machine as your Excalibur .I mostly use the 15" WOT Coil from Coiltek and I get unreal depth.The coil is heavy but if you balance your machine properly or use a Bungee than you can hunt all day..My PI Machine is a Whites Dual Field,,it's the machine a lot of the pro's use and when you get used to a PI you will see why..I am a Dig All person mostly,except for bobypins,,I hunt in All Metal with my Sovereign Detector and you learn the sounds but some other sounds are too close to Gold so I dig..With a PI you will dig a lot but out in the water from about a foot out from shore I don't find much trash.I would keep your Excalibur for sure,,if you want something lighter for shore and parks there's so many good machines available now,,read the forums,you'll find something that suits you..