I have a Lincoln SP-100 that does a great job. never used a Holbert, but my guess is that it will weld just as good as a Lincoln. be sure to purchase the gas option. It makes welding on car bodies sweet.
Hello,,,The thing that i have found as the major difference in MIG's is the wire feed "drive",,,Miller seems to have one of the best drives that there is,,,and this is critical to making a great weld. If the wire "stutters" during feed,,,it will produce splatter that you can't controll no matter what you try.Miller makes a really good MIG for the money.
I like the Lincon for lite work, mainly sheet metal to sheet metal, but for anything over 3/16th I use a Lincon 200. Hobart makes a good product, used one for a few years (a "175"), so I would say it's all your choice....they're both fairly good welders.
Like the others said, Lincoln, Hobart or Miller are all gonna be good machines. Hobart is made by Miller, but the wire feed drive is different in the Miller machines (but they're usually about $100 more). If you can swing the cost difference be sure to get the gas. It makes much cleaner welds. I've got a Hobart 135 and love it.