I just downloaded it on the Vita this morning. Haven't tried it yet though. Big Sky Infinity came out for Vita today as well. I'll probably pick that up too!
I love the time +/- and slo-mo mechanics. It looks fantastic on the Vita, it runs like butter and at full native rez. Absolutely beautiful artwork, design and originality.
It really pops on the Vita screen, the orange and blue bullets are so bright they almost get a 3D quality to them at times.