Talk he's available for £15-20m. That's got to be decent enough value for a 27 year old.
The fee seems pretty low for his quality if true.
Wouldn't be against it as personally i'm not that bothered with age,ceilings and resale values as some others are,more that the incoming player is of high proven quality now and fits the team.
If the player is young so much the better,but not every young player who reaches a high level early improves further.