I agree that Peter's con of Neal was brilliant - I didn't see it coming at all! And I wonder if Peter knew that it wasn't going to be Neal that read the file, but Moz? I have a feeling that Neal is still feeling way too guilty (and so he should) for breaking into the Burkes' home in As You Were.

I liked the ambiguity of the ending - whether Peter figured it out or El confessed doesn't matter to me. Peter knows now that Neal will do anything for Elizabeth, and by extension, for him.