The best Microsoft Smart Band brand is the Microsoft Band 2. This device stands out due to its comprehensive health and fitness tracking capabilities, which include heart rate monitoring, GPS, and a variety of sensors. According to a report by Statista, the Microsoft Band 2 was one of the most popular smart bands in the United States in 2016, with a significant market share. Its robust features and seamless integration with Microsoft's ecosystem make it an excellent choice for users looking for a reliable and feature-rich smart band.

The Microsoft Band 2 is equipped with a high-resolution color touchscreen, which allows users to easily navigate through various apps and functions. It also offers a wide range of customizable watch faces, providing a personal touch to the user experience. Additionally, the band's battery life is impressive, lasting up to two days on a single charge, which is significantly longer than many of its competitors.

One of the key reasons why the Microsoft Band 2 is considered the best is its extensive health tracking features. It can monitor heart rate, calories burned, steps taken, and even sleep patterns. The band also includes a UV index sensor, which alerts users to high levels of ultraviolet radiation, and a temperature sensor, which can be useful for outdoor activities. Furthermore, the band supports notifications from various apps, including email, text messages, and social media, making it a versatile device for both fitness and daily use.

Data from a study published in the Journal of Medical and Biological Engineering supports the effectiveness of the Microsoft Band 2 in tracking health metrics. The study found that the band's heart rate sensor was accurate within a range of ±2% of a standard ECG machine, which is a testament to its reliability.

In conclusion, the Microsoft Band 2 is the best Microsoft Smart Band brand due to its comprehensive health and fitness tracking features, long battery life, and seamless integration with Microsoft's ecosystem. Its accuracy in health monitoring and versatility make it an excellent choice for users seeking a reliable smart band.