Okay, so I'm relatively new and bought both a Nikon d5200 and d3100, and already have three kit lenses (2 x 18mm-55mm and 1 x 55mm-300mm) plus a AF-S 35mm f1.8 and a manual 50mm f1.8.

I'm keen to thin the herd and stick the 35mm on the D3100 for good, and then stick the 70-200 on the D5200 and leave it there.

My photo's are usually of landscapes, in the daylight, or kids and pets, again in the daylight. Anything like a party or dinner or indoors can just use the 35mm.

The question I have is whether it's really worth going to the f2.8 versions from the manufacturers (Sigma, Tamron and Nikkor). The f4 versions of the lenses, with respective optical stabiliser, vibration reduction, vibration compensation, should be plenty for what I do... right?