Greg Fertel of Pending Pinstripes has some more info on both players:
David Winfree, OF: Winfree is a 23-year-old who has spent his entire seven season career with the Twins organization. He has been considered a decent prospect before, but his walk rate really holds him back. He has posted a career OBP of .318, which will do a lot to kill a marginal guy's prospect value.I don't expect much from any of the three guys signed in the last two days, but you never know. Cash has signed some nice players off the scrap heap in the past few years.
He tries to make up for the lack of on-base ability with power, but it's not enough. He used to be a third baseman, but struggled there defensively and was moved to the outfield. He has a strong arm and can man right field, but his range is extremely limited.
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Royce Ring, LHP: Ring possesses a familiar name, as he saw some major league action with the Mets a few years back. He's a lefty who has had success against lefty batters throughout the minors, so he is a good guy to have around. He won't blow you away, but he strikes out a few batters and doesn't walk many.
CHONE projects a 3.98 ERA from Ring in 2010, and I'd take that in a heartbeat from a guy picked up on a minor league deal.