In reply to d508934:
Horrible textured wallpaper was often used to cover up really manky plastering. In our house, almost every wall was covered in the stuff, and all sorts of nasties appeared once we stripped it. I don't think it's possible to tell in advance what it's going to be like, except to think that the older the house is, the more likely it is that the underlying plaster will be anything between being a bit scruffy to virtually falling off.
I've never used a steam thingy for stripping wallpaper, but I have heard bad things if the plaster is in poor condition - the steam can strip the plaster as well as the paper, which isn't what you want! It might be worth doing a sample using old-fashioned soapy water and a scraper to find out what the wall is like underneath the paper before unleashing the steam.