Skywest gives a very professional yet laid back interview. I had a great time when I interviewed there recently. Your HR/Tech will vary greatly on your background/recent experience. Current 121/135 jet will probably eliminate the sim, and make the HR/Tech not to difficult, but regardless, know your stuff. I studied pretty hard for this, and even got some sim time just to be prepared even though I didn't have to do it. Seems like a nice place to work!