In six seasons in Cuba, Maya went 48-29 with a 2.51 ERA and in the WBC he's
1-1 with 0.87 ERA. In 10.1 WBC innings, he's allowed 3 runs (1 earned) on 9 hits, walked 4, and struck out 6.
According to this article by Jorge Arangure Jr., when Maya showcased his stuff at the end of last year he was throwing 88-92 MPH four-seam fastballs, two-seamers, sliders, curves, changeups, and even the occasional splitter.
Here's three videos of Maya pitching against Japan in the 2009 WBC: