Well, if the reason for getting a 7-string is that it would be easier to play, then I would definately stay away from it. But if you're into 7-string music (i.e. death metal, progressive metal etc.) then why not.

I find it much harder to play 7-string guitars. The neck is much wider and it's harder to play many of the chords because your thumb has to reach around that wide neck. Hendrix style chords (with bass note played with your thumb) are hard to play.

So you just have to think about why you would want a 7-string guitar. It most likely will be harder to play, so the only real benefit is that you get a wider range of notes to choose from - a range that is mostly used in heavier metal genres.

If you are interested in playing the guitar like a piano - with both hands on the fretboard - a 7-string guitar could be nice to allow you to reach the lower bass notes.