I would think that the chances of a Tailgater working inside an RV would be less than 50-50. I have had a Tailgater for about 3 years now. For me, it only works about 50% of the time when placed outdoors due to tree canopy at most campgrounds. So placing it inside would increase the chance of it not working. Besides, the Tailgater would take up the entire top of most RV dinettes.
You may want to look at a Terk amplified indoor antenna. It doesn't take up much room, can be amplified or not amplified and works well if you are within 30 miles of an HD over the air TV channel. I have one of those as a backup to the Tailgater.