I grew some of these last season and this is how I would evaluate what I got. I wondered how they would compare to regular butternut. For baking, my favorite is still butternut. To me, they still have the best flavor. But Butternut is still great for "pumpkin" pies too.
I'll probably grow them again, but not more than 2 vines.
The Amish squash is a little more watery but fibrous at the same time. They are also sweeter. More like an actual pumpkin I would say. Not the best for baking to me. But, they are very prolific and huge. They are really great for pumpkin pies and you get a lot more bang for your buck. To process for pies, I always peel the squash with a potato peeler (where possible; in some spots I have to resort to a knife) then remove seeds, cut into chunks and cook in a big pot with just a little water in the bottom. The squash provides a lot of its own moisture. Then I put the cooked squash in the blender and make it really smooth. I put the finished product in freezer bags (each bag contains what I think is enough for one pie) and use as needed.
They make really long vines and it's amazing how quickly the squash balloon up to full size once they set the fruit. Because of our really late frost last year, I figured they wouldn't make it. I always marvel at how the vine can send water and nutrients to a squash that's 15 to 20 feet away and so quickly.