Microsoft Band and Microsoft Health nicely illustrate the promise of Microsoft's "mobile first, cloud first" vision, providing a one-two punch of superior mobile hardware—the sensor-laden Band—and back-end services. If there's a downside to Microsoft Band, however, and there is, it's that this device is simply too unwieldy—physically, and in usage complexity—for most people.

But man, does the Band tantalize with promise. This is a true moon-shot of a product, and not a me-too copycat. If you're a fan of the software giant, please take heart in the fact that with Microsoft Band the company has finally taken a no-holds-barred leadership position. It's been following new markets for far too long.

Real-world usage is mixed. I've been using fitness bands for years, so I've developed an understanding of what's possible and, more personally, what's important to me. Through a succession of devices—two Nike FUEL bands, a Fitbit, a Samsung Gear Fit, and an Android Wear-based Samsung Gear Live watch—I've watched the market for these devices mature and, more important, have experienced the steady improvements that each has brought.

But Microsoft Band is not an evolution of what came before. It's an explosion of capability. And that is both to the benefit and detriment of any potential user. Just getting up and running with Band is complex and confusing. So, too, is using it.

Because I wear this product all day long every day—except of course when charging it, which happens far too frequently—I've had to adapt it to my own needs a bit. So I've turned off all of the non-fitness notifications for email, calendar and so on. It's just too disruptive. I've also spent a lot of time customizing what displays when, and where, on the device and find that, here again, there's just too much going on.

In this way, the Band resembles a modern smart phone. It doesn't just do a few things—make phone calls and send texts—it does an astonishing range of things, some automatically and some not. You need to work at it, and detuning some of the features I don't need or want is like that first week with a smart phone were you add and remove apps, halt unnecessary notifications on an app-by-app basis and perform other housekeeping tasks. You really need to work at it, and that's the opposite of what technology is supposed to do for us.

That said, there are some high points.

The biggest single unique benefit to Band that I can see is the automatic and continuous heart rate monitoring. I'm more addicted to this than I was when I first experienced sleep monitoring with the Fitbit I'm also still using. It's just fascinating to me.

Sleep monitoring is also interesting. But here, I see wildly different results than on Fitbit. (And yes, I'm monitoring sleep on both simultaneously.) Maybe it has to do with the bands being on different wrists, there's no way to know. But according to Band, I don't sleep well at all—it looks like an average of 5 hours a night for the past week, which makes no sense at all—and my "sleep efficiency" appears to correlate inversely to how much actual sleep I get. This is all very confusing. (And I wish sleep monitoring was automatic. This device is smart enough.)

Activity monitoring is more consistent. Fitbit doesn't have the same capabilities around workouts, of course, but core measurements like steps are consistent enough between the devices—and with Sensor Core-based Lumia handsets—that I feel like some accuracy has been obtained here.

Battery life is disappointing. Microsoft claims about two days of use, but it's closer to a day and a half, which means you really need to keep an eye on it. I lost a night of sleep monitoring because it died overnight, for example, and my efforts to reduce battery usage—automatic brightness, leaving clock mode off, and so on—haven't helped.

But hey, it's only been a week. More soon.