Jason Bowers is a former middle infielder in the Pirates organization. He's basically a Double-A/Triple-A utility man. Ronnie Merrill seems like an apt comparison, which is to say that you shouldn't expect Bowers name to come up during the season. Oh, and he's also nearly 31.
Jason Cromer is a re-signing. He's spent all but one season in the Rays organization. More filler. Cromer began his Rays career in 1999.