I've stayed here on two occasions, both times with friends (we stayed in the dorm beds). The camp has been referred to me by a number of friends traveling through Nairobi. Overall, it's a good place to stay if you're looking for cheaper and more relaxing accommodation in the Karen area.
The place is out of the way and would be a bit tough to find on your own if you took public (it's by Langata Road / Galleria, towards Karen on the Ngong Forest side of Langata - but I would call ahead to get good directions when you drop on Langata because it's a bit of a ways). It's about a 10 minute walk down a side street off of Langata, on the left side. It's not well marked, which I found annoying.
The grounds are pretty; there is a nice deck for eating/surfing the web (pretty fast)/socializing, so it's a nice place to escape the mayhem of Nairobi. The dorm beds were comfortable, but they squeeze 7 in a tent, and if you're on the top bunk there's not a lot of space to sit up (the canvas is right there). I've heard good things about the private tents, but I can't say from experience. Food is decent (nice little breakfast is included), but a taxi can take you to the Galleria shopping mall for somewhere around KES 200-400 where there's more variety (and where you can buy pretty much anything you might need in the Nakumatt supermarket. We used Wildebeest Tours for a budget safari, which was a good experience. Overall I'd recommend - not fantastic, but a solid choice, and close to Karen attractions (Elephant orphanage, giraffes, blixen, nairobi park).
Shared bathrooms clean, hot showers, etc.