Just to add a bit of fuel to the fire
I tried a chinese mig and most have probs with the wire feed motor/mechanism as they are really shit and not worth the bother unless you can get somebody to recommend you a good one that they have.
I just bought a 170 amp inverter arc welder as this is what we use at work(mine site).It is a quality brand Cigweld and has 3 year warranty etc,anyway the best part is the price as it cost me $399 about 240 quid and is absolutely fantastic.The quality of the welds is excellent and even my 3 year old could strike an arc with it as its basically one touch onto the workpiece and it arcs up.Although i will admit it is easier to tack your chassis with a mig