I highly recommend buying a good 110V unit with gas. You can use the flux core wire (as I have done for years) but having the gas makes your welds much nicer.
110V is nice because you can be mobile with it. This may not seem like a big deal until you realize that not all projects are within 10' of your 220V plug. Try going to Home Depot and asking for a 50' 220V extension cord
IMO, if you're going to get into big structural stuff that is thicker than 5/16" or whatever the limit on the 110V setup you're looking at you should hire a pro anyway. 99% of home projects can be done with the 110V.