These guys were super helpful. They did a data transfer for me from a dead 2011 Mac Air to a 2TB external hard drive. They literally made a clone of my hard drive for only $100. Now when I plug in the external to my new laptop, it's like a beautiful little USB of my entire old computer! So great. Apple Genius Bar WILL NOT do this data transfer for you. They only work on your computer if you can turn it on. Totally useless if your logic board is dead. The Tekkies are real tech geniuses. They take off the back and do the manual work of examining the physical parts. Definitely go here instead of a brand name store.