Well, you get what you pay for.
The Go-Pro is at first look very attractive, but detecing capabilities are according to people who used it below an ACE. Also a lot of trouble with mechanical issues. A foldable detector that does not fold back because dirt block the joints is just not the thing.
The XP is considerably more expensive but surely one of the top end machines available. It fits into a large backback but not into daypack. It is also very light: under one kilogram, which is important for air travel and backpacking. It is not complicated as long as you stick to the factory programs -> and those are already good of the rack.
The minelab CTX 3030 is according to many a notch better than the XP, but also offers bell&whistles I just dont need on an detector (GPS, wtf). You pay for it with an hold-you-breath price and it is an ergonomical nightmare (collapsible but even collapsed does not fit into a backpack; weight c 2.5 kg).
Your choice! I should add, if you fell like you are good at tinkering, the collapsible frame of the XX is sold separately and you could try to fit the detector of your choice on it.
Greets Namxat
Yes I have Deus, I like it. But no, no commercial interest.