Forget what they say; ground-based missions ARE fun!
Now I really had low expectations when I got this. I mean almost everyone dissed it because of its ground-based missions as if such a feature was a blasphemy to the Starfox name. Turns out it really isn't.
The gameplay is divided in 3 different types. First there's arwing (airplane) missions. Flying is as fun as ever and actually even better because of the nicer graphics. Some of the power-ups have changed for the better and you'll still have to deal with your team's cries for help and all.
Then theres the landmaster and the ground missions. The landmaster is actually far more interesting now because it can run over enemies and reach high areas with an easier to control hovering feature. As for ground missions, it can take a while to get used to but the different weapons you can use and the possibility to ride the other two vehicles during missions can make it pretty fun.
The only letdown are the really short story missions. Once you're done, all you can do is try to find flags or get better medals, which really isnt important except for little bonuses. You better have friends to play with because the multiplayer is great with many areas to play in and characters to choose from.
In short, don't let the "ground missions" prejudice get to you even if you're a die-hard fan of the series. If you're a real gamer, you'll try it out and you'll be pretty surprised.