Good budget deal in the middle of La Paz, pretty close to all the action. The traffic is a bit noisy and can wake you up in the morning (the traffic is horrible in central La Paz) — and they have a strange habit of cleaning the bathrooms at 8am in the morning — but otherwise, no complaints. Not the most social place I've ever stayed at, but certainly better than Tambo de Oro, where I was last night (doesn't merit a write-up, as it's not worth going to at all). If you want the real party scene, then of course you have to stay at Loki.
Rooms: clean and private, but noisy with traffic in the mornings.
People: a lot of Europeans, and a few Israelis — nice crowd, but not that talkative.
Staff: brisk, not that friendly, but they do their job.
Location: central of La Paz — strangely, it's completely surrounded by hairdressers (watch out when you walk down the street — they'll hassle you for a trim!).
Food / internet: no food (but there's a kitchen), Internet available for Bs. 4 per hour.
Hot water: not 100% reliable, but great most of the time. Watch out for electric shocks — always wear rubber sandals in the showers (as with many places in South America).