I have used the 250EX and it welds stainless and aluminum very well I have not done a lot of welding with the 210EXT except at Everlast Canada and it work very well but I got the 255EXT and like it also the 255EXT I like is the switching around from AC or DC just by setting the memory to each type of welding then us find the memory number you like and weld it switch all automatically to AC or DC, pules or not and you can use easy set up AC or DC it is nice also. I have not tried the 210EXT in the hidden options section but maybe next time I go to Everlast Canada. Good luck with the new 210EXT.
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