Dan Meadows is the most interesting of the three: He's a 24 year old left-handed reliever who has posted sub-3.00 ERAs in the minors each of the last two seasons. He struck out nearly nine batters per nine innings in a season split between Huntsville and Nashville in 2011, and walked less than three.
Butler is a 27 year old stalled prospect who posted a 5.15 ERA in 29 starts for Nashville in 2011. He's been in the organization since coming over in the Gabe Gross trade in 2008, and had a brief cup of coffee in the majors in 2009.
Arlis is 31, a career .237/.315/.329 hitter in the minors and only appeared in five AAA games for the Brewers last year in his tenth pro season, but you can never have too many catchers in camp.