100-400 v2 works well enough. Would expect similar from 400 f5.6 with perhaps a bit less distortion. Enjoy the time off hunting out the panos. Sounds like fun!
Curious as to how you will use the resulting pano images. I have a number that are bigger than 3x6, up to 8x12, feet at 300 ppi. Always find myself resizing the image smaller every time I make a print. Have been toying with the idea of triptychs to make a photo wall or two. Wondering if you have tried anything similar yet?