I have a 70-200mm lens. I would like to get a bigger lens but my price does not go above a 300mm (and probably never will). I would like to hear your thoughts on whether it would be worth it to get a 70-300mm to have that extra 100mm. I am fairly new to the DSLR world and appreciate your thoughts. Would there be a reason why I would want to keep the 70-200mm if I did? Thanks.