I started my City and Guilds level 2 in MMA this week. The college equipment is rather fancy and it took me a while to get used the the rods (Nexus 3.2) and the welder which was a fancy Lincoln multiprocess three phase thing with digital readout and a display screen. I just about managed a...
www.mig-welding.co.uk
You can't really go wrong with an inverter as long as it is putting out the amps that it says it is. Stay away from the really cheap ones for this very reason. Inverters weld really smoothly. They suck less juice and won't trip a marginal electric supply as easily as a transformer.
Never heard of a flama arc, it sounds cheap and chinese.
The Parweld is also chinese built, but it's a well known and supported brand in comparison.
Both will lay a simple MMA weld no bother.
An ok-ish 160 amp set like the Parweld will be able to run 3.2mm rods all day long, it SHOULD run 4.0mms but whether it will or not, don't know. But TBH you can achieve an awful lot with 3.2mm rods, it's the biggest size we use anyway.