I bought both the Panasonic 3D glasses and one of the cheaper $20 Samsung glasses (at a local Best Buy).
They both work fine with the Panasonic 2012 plasma sets, the Panasonic model has a built-in USB rechargeable battery, and the Samsung uses a cheap replaceable lithium coin battery.
The Samsung is a bit more flimsier and lighter, so the Panasonic model feels and looks more like regular sunglasses and is a bit more comfortable.
Its been recommended that the more expensive Panasonic 3D glasses is good for your own use, and get some of the cheaper Samsung glasses for guests/kids.
I found some really cheap compatible lithium coin batteries for the Samsung glasses on ebay, only $1.25 for a set of five that should last a year or two probably even with frequent 3D use of them.