I applied online. The process took 1 week. I interviewed at F5 (Lowell, MA) in Aug 2014
Interview
My sense is that the company is very well liked by the people who work there. Many folks have been with the company a relatively long time. That said, it is not a stagnant place and the people I interviewed with are top-notch engineers - seriously, the best of the best. The interview was long but not out of the ordinary these days: about 6 hours. I interviewed with seven people; most by video conference, which went well. All of them knew their stuff and most were very cordial. The questions varied but there was a strong focus on signal integrity, PCB materials, and the like. A recent SI hire is quite talented and will drill down. The local (Lowell) engineers are seasoned and easy to talk with. It's clearly a very high quality company. Do your homework.