Only place I keep in check most regularly is my underarms. I hate hair under there, especially in summer. In winter, I might get a little lazy though and grow it out a bit to stop soreness (never been sore before, but just in case). It's for hygiene over looks.

My legs I do... rarely. Quite frankly, I never wear anything but long jeans, so no one sees my legs anyway. I do it now and then to feel good about myself, but it's not important for me. Feels kinda good in summer though, even with jeans - you can feel the breeze on them a little better; in winter, it's nice and cold haha.

As for downstairs... uh. I keep it trimmed. For hygiene, mostly, at certain times of the month, and for when I think it's getting too long down there. I don't take all the hair off because it gets really irritated when it grows back (and I like downstairs hair anyway), but a quick trim and a little shape for the hell of it.