I have the same issue on mine. I'll be sure to try what others have recommended here, thanks a bunch!
Mine is a macbook pro mid 2014 model? 2.6Ghz intel core i5 , whatever the hell that means.. not a tech guy haha
... letters are always better than pro letters. You should go with ... a pro letter only if you can ... obtain. So go with a pro letter if you need and ...
It doesn't hurt to send some "feeler emails" to prospective profs. If they say that they are not able to write you a _strong_ recommendation, then go with the pro letters.