About the only problem with the Game Gear is the fact that it was large (although not compared to the Atari Lynx in either incarnation) and sucked up batteries pretty feverishly. It was a fun system. I didn't get one right away, but when I did, it was nice because it had games a little more complex and in-depth than the GB, including some RPGs. Sega probably didn't have the cash to launch a new unit in the mid-to-late 90s because of 32X and Saturn sucking up cash!
I've never used the Game Gear, myself; never have seen one. I imagine that if I'd ever managed to get one during its heyday, the Sonic games would be the focus of my attention. I wouldn't know too much about the downsides of using it, though.
