I didn’t know anything about him, but I did find this brief scouting report via Baseball America:
Allen throws four pitches, three of which grade as average at times, but lacks the one dominating offering to put batters away. He sinks his fastball at 87-91 mph and occasionally breaks out a swing-and-miss slider in the high 70s or a changeup in the same range. His curveball is less refined, but he’s around the zone with it and all his pitches. Wiry strong, Allen has a quick arm, but he tends to tire visibly by the fourth inning. Still, he’s worth taking a flier on because he’s a teenager who already shows a feel for pitching.
Here are his stats since going pro:
Considering that Miranda is not the type of player that you can really expect to get a lot in return for, this is not a bad player to get. He’s a longshot, but that’s better than another Miranda type.