He's miles ahead of Dempsey. There's a reason Dempsey wasn't considered at 10m and only right at the end did someone stump up 6m to sign him. For 6m half of europe would be over this guy.
Bigger interest? Chelsea have had a long term interest in him and so have United.
No big club came in for Arteta and even though he was turning 30 and had a broken leg prior he turned out to be a great signing.
Frankly a person who uses the argument that "No big club is interested in this guy" to come to the conclusion that a player is not good enough just has a poor argument.