I purchased a new Grand Design Reflection 5er on Monday, and installed a TST507-flow through system this morning. It was easy to program the limits and install. I had no problems what-so-ever getting readings and using the system.
The display is smaller than a deck of cards, and came with a window mount that I put right above the rear view mirror. The FW is 36 feet long, and I did not need a repeater to get the signal.
It was interesting to view the pressure and temperature changes as I went down the road today, and I really like the fact that if there is a sudden change, it signals an alarm so you can pull over BEFORE you tear the heck out of your fender wells.