Service in the Amish areas was always interesting. The conversion rate (to JWs at least) was practically nil besides some converts about 60-80 years ago (wow). There was a convert family of Zooks that went to the Hall I used to. I think they are all dead now as they were SUPER old when I was in my pre-teen years. I've been gone from there for about 15 years now so I have no idea if there have been new ones. I doubt it.
The area is extremely rural. Amish farms are very big. So you would spend a good part of the morning driving to see about 10-20 houses. I didn't mind it. Typically the groups would stop for a break or to do more town territory to keep the placement quota up. The Amish/Mennonites were very often home since they worked mostly on thier farms. Funny thing: Witnesses don't have a monopoly on the term "worldly" as the A/M's use it too.
There were great variations in thier adherance to rules within thier religions (driving cars, electricity, association with outside world, etc...). Witnesses I knew used to point to that negatively showing how *they* were a cult for it. Pot meet Kettle.
The conversations with them were usually interesting. They too know thier Bibles very well. So, I recall one time arguing with an Amish lady about hellfire. At some point she was shouting "the letter killeth". It was interesting that sticks in my head even still. I wonder if they were counting time on us since we surely didn't mind preaching at someone for an hour getting absolutely nowhere.