Hey guys just wanted to ask your opinion on a recommendation letter difficulty I am having. So, I graduated this past May and had been working in my lab at Penn for almost 2.5 years. I am the co-author on a publication that has yet to be accepted by a journal from a project I worked on my first full academic year. In short, due to results that didn't really come out well this past year, my PI said he would write me a "brief and neutral" letter and has written it already. I am trying to decide whether I want to use it or not. What do you guys think? I am applying to many of the top medical schools that emphasize research so I am thinking I should submit it just so they don't question why I don't have one. It definitely will be my weakest letter considering I know my other letters will be very good.