please be more specific. a welding certification without AWS in front of it is for the most part, worthless. there is also a difference in a true certified welder and an expired certification (if you dont use it, you lose it). im currently aws d1.1 and d1.5, and have held many others which are now expired because i didnt use them enough to justify keeping them.
and again i disagree. its not all about capacity, its about room for growth. for example, i can simultaneously connect a mig gun and an aluminum spool gun to my 210. as i go from steel to aluminum all i have to do is put down one gun and pick up the other. this isnt possible on the smaller and cheaper machines, and this is just one of many reasons i recommend getting a better unit to begin with. capacity, componentry, duty cycles, etc. it all plays a part and ads up to just an all around better machine. were it not for cost i would recommend the 255.