Don't really think the power factor correction would be worth the expense for an occasional welder. While it will save money on power costs for a commercial operation, for a hobbyist or other occasional user it may actually run up your electric bill slightly over a unit without it. You would be charging the power factor correction capacitors all the time whether you needed them or not, so if you didn't need the capacitors to moderate the large swings seen in commercial welding it would be a waste.
The DialArc 250 is a great stick welder and would probably be the last one you would ever need. Bought mine for around $500-$550, don't remember which, but there was a welding table (sorry affair), vise (given away), several electrode holders (kept) and several 100 ft. of angle iron included in that price.
EDIT: BTW the DialArc 250 takes a large breaker to run to it's limits. If you aren't thinking of doing that, buy a smaller AC/DC welder.
2nd EDIT: Just to give you another view on power factor correction, in the Miller's owner's manual for this machine @ 230v input the unit takes 4.4 amps at idle without power factor correction and 24.8 amps at idle with power factor correction. So, while you may save on your power bill if you are using your welder extensively, in a home shop environment you would be feeding a hungry dog that won't bark at strangers loading up your tools in the middle of the night.