Pros
Garmin's culture is relaxed but motivating. I've seen senior management dress up for Halloween, but we're doing serious work too. Lots of intelligent engineers, so it's a great place to continually hone your skills. They are committed to their employees and hire slowly to avoid the need to lay off later when projects finish. Garmin is improving its training offerings, both technical and inter-personal, and in the last couple of years has gotten much better in that area. Because of the various divisions and the vertical integration style of the company, there are usually lots of internal opportunities if you are not happy with your current position. Many of my coworkers have transferred in or out of my group from/to other groups. Overall, Garmin does a pretty good job of maintaining a culture that feels almost like a startup (outside of Aviation, which necessarily is more process driven).
Cons
Slow hiring means that we are always pretty busy as we could almost always use some more people. Promotions are still guided mainly by time, not skill level. Management can be slow on the public recognition of good efforts, but they are working on that.