Should i make a move with my best friends ex?

my best friend dated this girl for about 8 months. He is kinda a playa, he hooks up with quite a few girls. Now the girl he was dating lives a little over and hour away from us. I always talke dto her even when they were dating and we usually have pretty deep conversations. Now that they broke up she talked to me about him and i told her that i didnt think they were right for eachother which is honestly true. I am startin to have feelings for this girl and have hinted it to her. I talked about going on a date before i leave for boot camp since i leave from the city were she lives. She said i should probly run that by him so i dont ruin a long lasting friendship. I told her i was leaving anyways so whats it matter if he wants to ruin it over sumthin dumb. I also told her that since i will be leaving in a year, if i date anyone now it will be because i think we could have a long term relationship(aka marriage) I think we could make a great couple. Tell her what i think or just let it be?