I primarily use a Labradar, but run a Magnetospeed with the Labradar a couple times each range session. I find them both very easy to set up, and they agree to with 2fps of each other.
I prefer the Labradar because it doesn't contact the barrel, which allows me to use it all the time, even when sighting in or testing a load for group size. Since it doesn't affect barrel harmonics, I pretty much never shoot without the Labradar, and I find always having velocity info to be helpful. However, the Magnetospeed Sporter is easy and accurate, too, and you get a lot of chronograph value for your $180.