I have been there five times in the past year and a half. Unfortunately I cannot say it is a great place to go or stay I own a house with my wife in Cambita
Sure, San Cristobal ist not a tourist attraction, but we like it. It's quite safe (if people know you and you don't act as a typical tourist). I liked the authentic market (mercado), which at the beginning I found a bit frightening, but isn't at all. You'll find much better food there, than in the "Sirena" the former "Ol?" supermarket.
Everyday highlight was the ride with the "moto" for 20 Pesos, because there is always something to buy or a place to go to, or take a pizza home, from one of the best Pizzarias I know (sorry, I forgot the name, but it's very close to the main square and has a garden). "El Sita", a nice place to have breakfast and a beautiful Ananas milkshake (which takes a while to prepare, but it's worth waiting).
Can't wait to be back in San Cristobal