Fresca is a really fun and lively place to go, with noise and crowds and a great atmosphere. The ceviche is wonderful and you have got to have a pisco sour (or 2). BUT as another reviewer noted, their service is kind of lacking in that it can be slow and they can indeed be forgetful. I've been there several times and have to say I still recommend it in spite of one time when they forgot to put our dessert order in and it took 30min to get it. Great fun to go with a group but dont expect to be able to hear each other over the noise. By the way, desserts are mediocre but the rest of the menu is tasty stuff, especially the appetizers. I like the ceviche mixto, but the 4, 5 or 6 ceviche sampler is a great way to go. There is one with black squid/octopus ink that is extremely good.
My boyfriend adds: "It's true that the food is great, especially the ceviche, but the real draw is the crowded, noisy, fun ambiance. However, it's fairly expensive (easy to spend $100+ for a couple incl drinks) and you should know that high quality, Peruvian food of almost the same quality can be had for a fraction of the price at dive Peruvian restaurants throughout the Mission. WARNING: the pisco sours have a delayed reaction...WALK home."
Pros: Pisco sours, Ceviche, Raucous Atmosphere
Cons: Price, Forgetful Service