These are both great movies. they are both slightly different adaptations of the Swedish book Let the Right One In. LMI seems to follow the book a little more closely than LTROI but it seems to lack feeling and emotional connection that LTROI has. LMI is also more visceral and raw than LTROI which is more of a slow nuanced. If you are going to see either of these movies I recommend seeing both version and judging for yourself which is better they are both great but for different reasons.