Discontinued and replaced by the K15, the K10 Mini truly is mini. Its water reservoir needs to be filled before each use up to its 10 oz max brew size.
The K10 measures less than 11" in every direction with a somewhat narrow 6.9" width that was great when the K10 was first released but seems bulky with the release of Keurig's new 4.5" K-Mini.
Keurig has released over 70 different coffee makers over the years, and only about a dozen of them are still in production and supported by Keurig. Those in-production models include both the K15 and K-Mini, making them both preferable to the discontinued K10.