In what ways do you consider him similar to Giggs? I don't know much about Giggs' early days, but I have the impression he had a furious pace and acted much as a typical winger seeking the end line to cross.
Whilst your previous post saying that James is effectively a winger is true (that's were he always played for us - we have been playing 4-3-3 for years), I still maintain that he would be better in a more middle role. His pace is nothing like what I've seen from Giggs' early days (he's not slow either, I'd call it an average pace for a top attacker) and even when we used him in the left he rarely use it to cross.
He seeks the middle ground all the time, whether he's on the left or the right, and that's more of a liability when he's in the left as he loses a lot of passing and shooting ability that way. It's quite obvious now with Hulk gone and with James shifted to the right that his productivity is increasing at an alarming rate. He his a good dribbler, but most of his effect in the field is seen through his great shots (something that he can still yet improve) and assists, mostly through ground openings, not crosses. He crosses well from dead ball positions though.
To sum it up, I think he's worth a lot more on the right than the left, and probably even more in the middle, behind the strikers in an advanced midfield role. The later is just an unconfirmed gut feeling though.