In a little dilemma. I own a 500d and want to upgrade my multi purpose Canon EF-S 18-200mm lens to a wide angled lens like the 16-35mm L series lens but putting it on the 500d will not serve its purpose as its not a full frame camera. I do plan to buy a full frame camera (5d mark II) in the future but won't have the money to buy it before my trip to japan. Would you still go ahead and buy the lens or not? suggestions would be great. I've read/watched alot of reviews and would love to own the 16-35mm lens.