Hey Dazza. Deciding what to buy will drive you nuts :/
Before even thinking about opening the wallet do your research as to what you are going to chase, where, how much of whatever you expect to find, blah, blah, blah and then hire the models you have narrowed it down to. That's my best advice
The rest is just stuff that I have learn't on here along the way.
SDC - decent price, wireless with the Pro Sonic or others, not entry level as far as performance but really basic to use - the machine does the hard yards. Lots of people have found lots of gold with them although mainly small pieces. And I know where you might be able to buy one in a month or so
GPX series - never used one but I get the feeling they have a really large learning curve - especially if starting from scratch. Extremely versatile considering massive coil options. Happy for someone to correct me on this info.
GPZ - awesome machine. Massive outlay. Reasonably easy to learn with a bit of reading and trial and error.
Gold Monster - an unknown but a reasonable price, provides discrimination capabilities, will be interesting to see reports if it ever actually gets on a shelf.
And in your Intro you mentioned chasing WW2 relics, etc. The above machines are gold machines, not relic/coin/treasure machines although they will obviously detect them. But something like a CTX 3030 then gives you target information that the gold machines don't.
And then there are all the other manufacturers. VLF, PI, ZVT??? The detectorprospector forum also has a lot of good information re: different technologies - but you could honestly read for 6 months and be more confused than at the start
But as I said at the start, I think basically deciding on what is going to suit your needs and then hiring those machines or going out with a club is the go. You might not actually like detecting
Best of luck with your decision. :Y: