As trimmers go, this is fairly decent. It's not too wide, so you can easily access each nostril, and the trimming action feels adequate. I have only used the nose trimmer function, and not tried the eyebrow combs.
It took a little getting used to the device at first, just because the shape of it makes you think it could be easy to cut yourself. But, I found it very safe to use.
I didn't give it five stars because it still takes quite a bit of time to trim all the nasal hair, but the results are very good.