Hi guys, thank you for the responses! To answer your questions:
1. APS suggested that I use the APS-13 because Ed believes I need a very directional antenna to fight multipath to a particular station. I tried a 70" 6-element Radio Shack FM antenna, and got better (acceptable) results than my roof-mounted omni, but still not quite as good as I want. The APS-9 would no doubt be an improvement over the RS antenna -- I think Ed is just playing it safe here. Additional gain isn't the issue, but more tightly focused directionality is.
2. APS does sell a rotor, they have just two choices, one with and one without remote control. I assume they can do the job.
Anyone out there who has used/installed the APS-13?
Thanks,
Eric