Ugh, I don't get why people want rechargeable batteries inside controllers. First off I prefer to use wired only so I don't even have to worry about it but if I am using wireless I'd rather have the option to throw in some AA's if need be.
Because of choice. Battery dead? Swap. Especially useful when I'm sitting far away from the TV and don't have to plug in the miniUSB cable into my controller.
Also, I got a play&charge cable for about 2,70 dollars, and you don't even need a batteries in the controller for it to work, the controller will become wired essentially.
The way I game is on a 60", about 3,5 meters from TV on a couch. Like I said earlier, it's much more convenient for me to swap a battery than to move closer to my console and grab a cable.
Well the PS3 controller and I assume the PS4 controller runs through the wire if you have it connected and only goes wireless once you disconnect it. As someone who mostly has hers plugged in most of the time it just makes sense to just unplug it real quick if I'm going to use it wirelessly for a bit. I imagine the PS4 manual will have instructions on how to replace the battery like the DS3 did should it ever die out but that is yet to be seen.
Another indication of the fact that PS3 controller runs through the wire wile connected is that when you disconnect the wire, the controller won't work for a second or two because it'll be connecting wirelessly (indicated by all the led's blinking).
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By the way, regarding the Sony Smash Bro's stuff, people seem really traumatised by it. Is it because the game is so bad or is it because the idea itself seems better in the imagination than in real life?