I have had a number of Yaesu radios and I also went with the FT-897 for the motor home.
I looked at the ATAS but after doing some reading I decided to revert to the way I used to have an IC-706 and went with the AH-4 tuner and a standard 102" whip. That way I could ad wire to the antenna if I decided I wanted more bands. I knew that the AH-4 was a very fast and versatile turner from previous experience and with it I had more options.
The overall costs, even with an ICOM to Yaesu interface for the AH-4 was about the same. And having had a couple of screwdrivers in my time I learned that they are not a maintenance free item and AH-4 is quicker to tune if you band hop.
Enjoy the radio, they are nice little rigs.