the mouse batteries can go fast, but i use rechargable's so its not an issue for me, the keyboard lasts forever it seems, the key though, is to turn them off whenever you are not useing 'em, which i personally do not do because im lazy, but you can get some great battery life out of them if you turn them off, and it doesnt take long for it to reconnect so its really not that big of an issue, if you have the $ i would go for at least the keyboard, but i am glad that i have both with my pb and they work great