I ended up getting the ryobi 4.5". There was a $30 model and a $40 model, and the $40 model seemed to be more adjustable and also came with a carry case and a grinding blade, a wire wheel blade, and a sandpaper flap blade.
I've had ryobi tools in the past and been quite pleased with how they held up. Of course, I sold them all during a time of unemployment, but they were still good tools.
Added to that was vanguy67's endorsement, and I was sold. It was even worth the aggravation of dealing with the mall traffic on the north side of town.
Now I just need an excuse to use it. lol