Service and advise is worth the couple of extra bucks you'd pay, by far. My local guy is great, he's saved me far more $$ by giving good advise than I'd have ever saved at the box stores or on the net. If there's any question he can't answer, he gets on the phone to his parent company's experts, their shop techs, other local weders that deal with him, or Miller's tech experts. The guy is like a pitbull when presented with a problem...he never lets go. It doesn't matter whether the question is about a $2k machine or getting a pound of the correct filler metal. He just wants to help his customers produce the best welds possbile. That's money in the bank IMHO.
Shop around for the best dealer as well as the best machine. Somebody who's knowlegable and willing to spend the time with you will make life alot easier,