He's not as bad as many make out. I remember just before his transfer to Aston Villa, we were very much in the mix. Unfortunately at the time he opted to go to Villa. Did he do right for his career? Looking back, probably, yes. He would certainly have gotten games for us back then however he wouldn't have developed into the footballer he is now (Villa offered him extended game time, I believe here he would have been on-and-off).
He's homegrown and for an England international he's extremely cheap. I disagree with those saying he's as good as Fernandinho (someone I rate extremely highly, ultimately one of my first names on the teamsheet), however, I do believe he can offer something to the squad.
If we were talking £20,000,000+ then I wouldn't be too keen, but for £8,000,000 - 10,000,000, go for it.