I'm looking to possibly upgrading from a Minelab Musketeer Colt to a Sovereign or Quatro. Or just adding a larger coil to my faithful colt.
I'm concentrated on parks and yards.
Excal 1000, Excal II, Sovereign GT, CZ-20, Tiger Shark, Tejon, GTI 1500, Surfmaster Pulse, CZ6a, DFX, AT PRO, Fisher 1235, Surf PI Pro, 1280-X, many more because I enjoy learning them. New Garrett Ca
I've heard good things from both the Quatro and the x-terras. I purchased my explorer used on ebay with some extra coils and got an amazing deal on it, so don't count eBay out!
I use both the Musketeer and the Sovereign and the Musky is the better machine on my (bad) ground. I can detect quicker and deeper with Minelabs sleeper machine. If you decide to go for a larger coil I would go for SunRay or similar and not above 12.5 inches. More depth than the Minelab coil and lighter.
If your interested in wet beach work then a switch to twin or multifrequency or P.I. would be needed.
Since your main thing is parks and yards, your'e probably in good shape with the faithful Colt, might get a different coil, but you probably don't need that, the 8in? coil usually works fine for me, but yards and parks you really don't need all the bells and whistles, and then you got a long learning curve to start (My Opinion)