Hi - we have a Camos dome fitted on the roof of our van, great bit of kit. We chose the dome as we caravan a lot in the winter and, in our part of the country (NE Scotland), this tends to equate to lots of windy conditions. Friends have a standard roof type dish and have problems in wind and also snow - neither of which affect the dome. We chose the Camos because it can relatively easily be transferred from one van to another, which our dealer did for us this year when we bought a new van.
Only once had a problem with regards to a signal and that was on a forest site where no-one could get a satellite signal.