What they got right: Having Paul Tobin write seems to always be a good thing. Iron Man does look better in FF colors that Ghost Rider–in fact they all do, but I like blue and the black comes out nicely, especially in the armor and Spidey costume. Of course, I always prefered Spidey's black costume, just not the shape-shifting, brain-eating one. Hulk wearing the Thing shorts works as well. Wolverine's gameplan is believable, as is Tony's attempt to snag himself some new armor. Bruce's fate is nice for a What If?, even if it wouldn't work in the MU Proper for obvious reasons. The story's ok, and filled with what I like about Tobin's storytelling style. However…
What they got wrong: The Infinity Gauntlet was a major event in Marvel (back when such things were rare rather than coming out one after another like they do today), and pushing it into a one-shot story feels packed in. We're really supposed to believe that these four (well, five, later on) could do in the course of a few hours or days what it took most of the Marvel Universe to attempt originally? Also, I wonder if Ghost Rider (who really looks out of place in a typical FF uniform) being replaced with Iron Man was due to pushing the movie characters (or alternately using them to get people to read the book, which makes grey Hulk an odd choice to stick with) or Paul having no interest in Ghost Rider.
Recommendation: I was never a big fan of the Fantastic Four, but I do like three of the four characters here (is there a comic not featuring or at least mentioning Wolverine and/or non-fascist Tony this month?), and the Iron Man and Spidey suits just look good in FF colors. Besides, it's Paul Tobin. That should at least be worth a browse. However, it's closer to three and a half than four stars.