Lincoln SP-175 or ProMig-175

[LCAC_Man]

I did some searching on this, it appears that there is no major difference between these models other than the $200 price difference (SP being more expensive) on ebay? Anybody come across any more detailed info? If not I'm going to go ahead and get the Pro-Mig175 and save myself some money.
http://cgi.ebay.com/Lincoln-Electric-MIG-Welder-Pro-Mig-175-K2280-1-NIB_W0QQitemZ7615657062QQcategoryZ113743QQssPageNa meZWD1VQQrdZ1QQcmdZViewItem
http://cgi.ebay.com/LINCOLN-SP-175-PLUS-MIG-WELDER-K1642-3_W0QQitemZ7561651924QQcategoryZ113743QQssPageName ZWD1VQQrdZ1QQcmdZViewItem

[4xFreak]

The 175 plus has the variable heat control, while the plain 175 just has five different settings.

I have the regular one and am happy with it so far. I'm sure it would be nice on some stuff to have the variable control, but mine does what I need it to do.

I think I remember reading on here or somewhere else that the variable control can be adapted to one that didnt come with it.