One of the biggest lessons I learned from shooting these photos.......... no matter how much you brush things off, or blow things off, dust is always going to be there.
There's only one thing that would stop me going for this lens over say the Tamron 90mm or Sigma 105mm and that is the lack of vibration reduction. I don't find using a tripod practical when going after fast moving bugs and if I can avoid having to use a flash I will, so VR would be really useful to me.