Cheap
Easy to use
Long battery life
Fairly accurate
measures bps
Weaknesses:
Only measures 200 to 400 fps, really not a big deal at all.
Review:
Bought this for outlaw games, work very well, in 10 minutes everyone is dialed in an playing. At $70.00 or so bucks it is well worth it to ensure safe games. Also measures bps which is cool, you do have to have the gun ramped up when you press to get bps count, which if your alone can be tricky. Overall great product for the money, and as you can see the weaknesses I listed are really minor.
Conclusion:
Highly recommend, cheap, accurate enough, easy to use.