I had mixed feelings when I finally had the opportunity to watch Little Ashes. First, I was extremely interested since I like biopics and it was about artists I admire - Dalí, García Lorca, Buñuel... Yet, I also feared it would turn out to be a movie that wants to be so artistic it goes wrong (like Klimt with John Malkovich - not only it was boring, it was also confusing and, quite simply, a terrible waste of time). Unfortunately, I was more or less right - it could have been way better, more dynamic and less overwrought. I especially disliked the portrayal of Dalí - I understand it's hard to bring to life a man so extraordinary, revolutionary and weird, but it simply left me unimpressed. As for the actor playing Buñuel, I would say he was alright, nothing special though.
However, I do recommend this movie because of the depiction of García Lorca - Javier Beltrán was exquisite! With basically no experience in the film industry (prior to the film he only starred in one series), he managed to conquer all and played his teen idol co-star off the screen without making any efforts. You might say here that García Lorca is an "easier" character but then again, you should not forget he is a national hero in Spain.
Beltrán reminds me very much of Nacho Martínez; I hope he will get the roles he deserves because believe me, a talent like this does not come around too often.