I have this double kickstand on my commuter. It has 2 distinct advantages over a single:
1) you can load up rear panniers unevenly (more weight in one pannier than the other) without the bike tipping over, since the stand keeps the bike left-right balanced, and with a wide kickstand stance.
2) because the rear tire is completely off the ground, you can fully pedal the bike by hand and make derailleur adjustments without needing a bike stand.