We did it! It was fun, but really cold! Make sure you do lots of layers, because its not very strong. I really like that we did it though, so some day Blue can touch it and see how big he made me!
My DH and I literally just did one about 2 hours ago. We didn't buy a kit; we just went to our craft store, bought 2 rolls of plaster of paris cloth. I found instructions online to do it at home. All we had to do was cut it into strips, rub vaseline on my chest & belly, cover the area with old sheets, wet the strips and DH put them on me. Then I had to let them dry for 30 minutes while I sat there and then popped it right off and jumped in the shower. It's drying right now (I think it will take a few days to really dry well) then I'm going to trim around the edges and paint it. Total time took about an hour including clean up and it was a litte messy. But, I think I think it will be a neat thing to have, was cheap to make and fun to do especially with DH. You can buy kits to make it but it's really not necessary. If you haven't had your little one yet I say go for it!
Re: belly cast
https://www.proudbody.com
We did one. It was really awesome. My DH did the cast with my Mom's help. We did it in the nursery with world beat baby music on.