I know most would pick the Gameboy but some may pick another. Vote and then tell us why you picked your pick and which one you hate. I know this has been done before but this time I wanted to include some more obscure handhelds in the poll. Have fun and enjoy.
My best will go to the Gameboy. The Game Gear is close for screen features and it is very comfortable, but I dont like any of the games, and the GB had the best games and the most that I enjoyed. I will make an honorable mention for the Supervision (Watara Version) the games sucked but the system has a nice screen and was powerful, and would be very nice with some good homebrew games.