Must have been a bad fall. I have kicked my n73 across a concrete car park twice now, and just got scratches on the side. Not as robust as my wifes 3210, which she ran over in the car twice (once in once out of the parking space). Had to get a new cover for that.

I would personally never buy something for what it could be, always buy it for what it is now, and if it gets better that is great.
Other than that I would call it a very personal thing. The N95 is pretty much like your n73 with a few more features, the iPhone is very different. It would be impossible to say without knowing what you do.