I enjoyed watching the show. It could have been a lot worse.
1. Yes, their terminology is ridiculous. And sometimes it gets old. But hey, if they weren't "kooky guys" it would get old real fast. Unlike most metal detectorists I've met, they have personality.
2. I don't think there was anything truly "fake" about the finds. If they wanted to fake it they would have been finding gold coins and such. There was absolutely nothing spectacular found despite the fact that they got to detect some premium sites. All normal metal detecting finds with some trash thrown in here and there.
3. The King George coin was probably found before they actually recorded him saying that he wanted to find a King George. It's all done for the sake of the viewer. He probably wasn't even expecting to find that coin and afterward they decided it would be cool to have him claim that he really wanted to find one. Remember, they can show this stuff out of sequence. The "sit down interview" portion of the show is always filmed after the field work is done.
4. The values they quote for each item are obviously inflated. We all know that you can't take any random .30-30 brass and expect to get $1 for it. HOWEVER, you could probably expect to get $1 for a piece of brass that was found in a specific place and had a neat piece of history behind it. If that brass really was from a specific prison riot then it is easy to believe that they could get $1 apiece or even more from interested collectors.
5. The "bets" they have help keep the show interesting. Without a little drama people are going to get tired of watching really quick. These guys are willing to "take one for the team" and do something wacky just to keep the show lively.
6. Their digging technique sometimes left a lot to be desired. I don't think I saw them dig a single plug. That's probably to be expected in the SC sandy soil. But up in Montana I would have expected to see some real plugs and not just them stabbing at the dirt. Of course, they weren't on any well manicured lawns so perhaps they didn't feel the need to be too careful.
7. It would have been nice for them to show more junk being dug. That's the reality of metal detecting. At least they showed some junk on the table when they were all done.
Overall, my kids and I liked the show. It's not exactly "reality" but I don't think they are purposely planting finds in order to look good. It's about as realistic as Gold Rush Alaska, American Pickers, and many of the other shows we enjoy watching. Then again, we know it isn't 100% real and don't expect it to be.
In general it was actually as realistic as it needed to be. They spent several days digging and found what most people would call "a whole lotta nothin'". Most people who aren't into metal detecting will walk away from that show wondering why on earth anyone would waste their time trying to find wheat pennies, bullets, buttons, and other such "juice".

I don't think too many people left that show thinking "Man! I have GOT to get me a metal detector!".