Unless you need to protect something with a bulb (projector) or a hard drive (DVR, HTPC), you don't really need a battery. They are nice to have if you just happened to be using your system when the power cuts out since they'll give you time to shut down cleanly. Pretty much any of the home theater APC products will be sufficient to protect your equipment from power spikes when the power comes back on. The specific model you get really depends on your power environment (lots of brownouts or blackouts?) and your equipment to be protected. If all you want is to make sure your receiver, blu ray player and TV are protected, any of them will do (P- or C- type). If you have lots of brownouts or sagging voltage events, then a model with a variac (H- type) would be a good idea. If you have something that would be harmed by a sudden power loss, then you need a battery (J- or S- type).