The HK VP9 is HK’s third striker fired pistol in their history and their current striker fired pistol under their existing lineup. The VP9 holds 15 rounds of ammunition, while the VP40 in .40 holds 13 rounds. The VP9 has an excellent trigger and ergonomics. It competes directly with the Glock 19, Smith & Wesson M&P9 2.0 Compact, CZ P10C, and the Walther PPQ.
The VP9 provides a number of neat features, including the ability to change out both the backstops and the side panels on the grip to larger or smaller sizes to accommodate different hand sizes. It also has two polymer extensions on the sides of the rear of the slide to make it easier to grasp and rack the slide in wet conditions.
There are also subcompact version of the VP9 called the VP9SK. The SK comes standard with a 10 round flush fitting magazine, but also accepts the larger 15 round magazines of the VP9, although they will protrude beneath the gun. The benefit here is that you can carry the VP9Sk for concealed carry, with a longer 15 round magazine for you reload. Or, you can carry both pistols at once, and then use the same magazine for your reload for either weapon.