Makro/Jeohunter are old Turkish brand names. They do work (though I would bear in mind they also make Bionic Systems, Long Range Locators). The more expensive machines do seem to get sold on after six months or so half price. All depends if you need to find caves/voids. If not stick to a coin/ring machine and save some money.
Latest other brands you will be hit with soon are the AKA's (which are quite well made) and machines from Pirate Detectors like the Black Devils as someone will want to make a quick buck.