I've only had two relationships in 6 years, so I'm not that experienced.
As everything, I really think it depends on the person, but generally speaking Japanese men are more shy compared to Western men.
Not many kisses in public, or holding hands in front of friends.
That said, they are very caring in private (at least so was my ex!).
Maybe the men out of Tokyo can be more traditional, but nowadays, apart from the shyness, I'd say Western or Japanese, "all the men are the same"