Some 12's came with factory rollers. Pete says production switch from flat tappets to rollers was April 2012. My 2012 came with factory rollers. The only way to tell for sure on a 2012 is to pop the valve cover off and have a look.
Yup, no reason to avoid it if it's a flat tappet version as long as it hasn't been ridden to death. Quite simply if it's done less than 20,000 miles it is *almost* gauranteed that while there will be damage it won't be too far advanced and if the bike has a full service history a kit will be provided.
If it hasn't got a FSH then it will still need rollerising but the cost for a 2012 isn't absurd, a grand or so should cover it, just factor it into the purchase price.
Make no mistake though, it will need doing if it isn't a roller bike ex factory.
Pete