In years gone by we've had Rooney, Raul, Anelka, Kluivert, Del Piero, Ronaldo, Fowler, Owen etc. At the age of 21 they were established players at top clubs like MU, Arsenal/Real Madrid, Ajax/AC Milan, Juventus, Barcelona/Inter, Liverpool etc. In fact before turning 22 they'd all won trophies with their clubs. Bendtner isn't in the same class IMO.
its worth pointing out that almost every last one of those strikers you mentioned got worse as they got older and injuries, lack of effort, money and whatever else caught up with them.
This utter myth that you get better as you get older is beyond a joke. You can also include Eto'o, Messi, Robinho, kaka, RVN was banging them in just not here, RVP was banging them in 3/4 years ago as he is now, just injury free(ish) now, and most of the worlds best strikers, most of them were as good when they were younger.
Often the difference in older players "seeming" better, is often down to foreign players very often playing in their own countries leagues for years before getting moves around, for instance RVP was great at 18, but we didn't see him till later, same can be said for many of the worlds top strikers, but you see RVN suddenly all the time when he's what, mid to late 20's and you assume thats when he got good because thats when you started watching him.
AS for not putting Bendtner in the same class, I agree, thats fair, i've yet to think he'll be "that" good, but again the names you've listed are probably the top strikers in the world, not being in the top 30 strikers in the world doesn't make you terrible, nor do many of the best clubs in the world have more than 1 or 2 of the best strikers, almost all have less good strikers for rotation and injury cover. Bendtner with few appearances, no form, no help has shown more than enough potential to be more than good enough to be a 3rd choice striker for us, if he grows into a 1st/2nd choice is yet to be seen, doesn't mean he's crap though.
