with great care and a lot of time.... you can use both three surface types on a single model, (and convert em to oter type futher tweack, reconvert, etc...).
What im trying to tell you is that you should mix all them, using the surface type that allows you to model each single piece of the model faster and eficientlyer (which is a matter of what are you most confortable with)...
looks like i would use mainly subd in polyproxymode for the phone tough...