Went and visited my sister awhile back for the holidays and she just went ecstatic with the fact that I had a MacBook. (I think she is more intrigued about the slim design than performance). And she mentioned that she would be up for a totally straight trade. Is it worth it? Would it be something worth doing? How much more powerful is the Late 2013 MacBook Pro compared to the regular 2015 MacBook? They're both 256gb models. Just curious if its something I should totally look into doing.