I do not have cleaned my D700 in a year. Just the normal menu settings for automatically cleaning the sensor when the camera goes on or off. I shoot in every kind of weather, change my lens everywhere and until now no problems. (After this post I suspect I will got them:biggrin
The only thing I always do is when the lens is off, I have the sensor facing downwards and in that position put on the lens. Maybe that helps?
Read you posts a little late. I have been mto Europe several times the most recent was last summer. My experience was very similar except I only took 1 camera the D90 and changes lenses. I had a small blower as well as a pen sized cleaner with brush and pad. The lenses used most frequently were the Nikon 24-70mm and Tokina 11-16. I took the 50mm 1.4g and 35mm 1.8g. The 35mm AF motor broke early in the trip, but didn't use the 50 or 35 much. Whether in the city or country side the 24-70 or 11-16 worked great. Absolutely no need for a telephoto.