I'm using the Alpa with a ground glass back and reflex viewer for composing. You can easily pop this off and replace with a film or digital back when you're ready to shoot. This method is only useful of course for more static subjects like landscape.
Also, Jeff Hirsch, of Fotocare in NYC is an excellent source for anything to do with Alpa.
After trying a friend's Alpa I'm thinking about buying one but I'm not happy about the finder because what you see is definitely not what you get. Does anyone have real life experience with the Linhof Multifocus Optical Viewfinder 6x9 used with the Alpa?