I use Amsoil MCV in my engine and primary on my 2008 Ultra and I use Spectro for 6 speeds in transmission. I like the MCV in the engine as it really seems to make it run cooler and it provides great protection for when it gets a bit too hot as this oil does not break down at the temperatures that regular motor oil does. A lot of people stick with the HD formula oil for primary and that works great but I like the MCV better.
On my 1990 I used MCV in engine and primary and Amsoil severe gear in transmission and it worked well.