I've got one, and a KM-110R. It has less power than my BR-500 backpack (which is stronger than a box store backpack, but way weaker than a full size pro backpack).
BUT, it has more power than my BG-85 had, and that was about as strong a handheld as you could get. I hear that if you have a KM-130, it gets even stronger (and with a KM-90, it doesn't blow quite as hard).
The downside, is it is also way heavier than my BG-85, but since I use the neck strap, I really don't notice the weight any more.
It IS funny looking, but it does work well, and blows as hard as they claim. As a homeowner, I bought it to replace my BG-85 (which I then sold), so I would have one less engine to maintain, and I've been quite happy with it (although it really doesn't get used nearly as much as my backpack).