I only switch phones every two years or so as my contract allows. This will be my first phone by any manufacturer other than Motorola. Star-tac --> Razr --> Rockr --> Droid --> Bionic. My wife had a Samsung flip phone a long time ago that was nothing but crap. I'm really hoping that Samsung has it's act together build and quality wise now. I'm loving what I see as far as specs go.
My Droid Bionic's days are now officially numbered. Just pre-ordered the Black Mist S4. Looks like I get to hold onto my unlimited data until it ships too. I was going to wait until after Google I/O, but I determined that even if they announce something at all, I want to take a break from Motorola for a bit. Worst case scenario, if something wows me, I sell off the S4 while it's still hot and bite the bullet off contract, but I doubt that will happen.