I would like to add a 300mm zoom lens to my little collection (eventually). The 2 lenses I am comparing are the Nikkor 55-300mm dx lens, and the Nikkor 70-300mm fx.
I already have the 18-200mm, so I'm not worried about the difference in zoom ranges. Both lenses have identical apertures and similar minimum focasing distances. The FX lens has IF-ED, while the DX lens is missing one of these acronyms.
The FX lens isn't *too* much dearer, but I normally steer clear of FX lenses, as I think you're paying for something you're not using (ie a larger sensor, larger glass).
I would be using the lens to take pics of my kids in situations where you cannot get in close (eg, sports, parks etc). For this reason I don't want a large aperture (and decreased depth of feild-I wanna capture the whole image), but I still want nice sharp images.
Your thoughts are greatly appreciated