A couple of years ago I bought a traditional transformer 180A mig for 500 quid because, in my opinion, similarly priced electronic units weren't trustworthy enough at that point. This past few months I've been aware that some of the cheaper (500 quid) electronic ones are proving themselves to be pretty long-lived, but still only as good as their warranties - who knows if a cheap importer will still be around when the machine goes tits-up.
Right now, I'd look seriously at an electronic machine, but for 500 currency units I'd still buy one of the last transformer rigs (they're getting phased out in the EU from next year), but that doesn't help you if you want light weight.