Justin Hampson is a 32 year old lefty reliever that was let go by the New York Mets earlier this week (as they removed him from their 40 man roster). Hampson threw 10 innings for the Mets in 2012 after not being in the big leagues since 2008 (including a terrible 2010 with 2 independent league teams).
His delivery is strange, but he isn't a sidearmer. I found it surprising that he has had basically no splits over the last two years in AAA. I also found it surprising that he didn't have a longer injury history as that arm motion looks really messy.
When I saw him, he was throwing about a 84-88 MPH fastball right down the middle. Even though he is a lefty, he really couldn't get inside to lefties. He has to keep it low, where he can get some sink on it (though Pitch F/X says he doesn't throw the sinker much). His velocity has dropped since he was last in the big leagues in 2008. In 2008, his 4-seam fastball was 88.13 MPH on average. In 2012, the average velocity was 86.50 MPH.
Hampson threw a lot of 76-78 MPH pitches in the outing I went back and watched. That velocity looks like his change, but it breaks like a decent slider.
The actual slider I saw him throw was at 83 MPH and it was a baby slider. Without Pitch F/X, I would have flipped the two, calling the harder one the change because of movement.
I think I saw the curve once in the outing I watched, and it has some really nice movement. He is very slider heavy, but I think he should throw his curve more.
This may be why he doesn't have big splits in this minors at least:
I can see why the Mets let him go. It is hard to see how he is worth a 40 man spot. He doesn't have the splits (mainly he isn't effective enough against left-handed batters) to be a situational lefty, and he doesn't have the strikeout rate or velocity to be a good reliever that you would let face both lefties/righties. At this point, he is a low leverage reliever type, but he has never ability to have long outings to eat up junk innings. It is hard to see his value at this point, especially on a 25 man roster with a 7-8 man bullpen. He is the kind of guy you invite to spring training, hope he has a good year in AAA, then try to add him on the 40 man roster in September if you are competitive to try to help the bullpen.