50mm f/1.8 mK II ... or ... 50mm f/2.5 autofocus macro?

[Jemook]

help me out here boys and girls.

which one? i hear the 2.5 has quality similair to an L lens, and I probably would stop down the 1.8 to at least 2.x to get a decent image with it anyways..

[FrenchAmateur]

That's true. The 1,8 starts to be really good at 2,8.
There is another alternative, the excellent Sigma 2,8 50 mm macro, better than the two Canon lenses, and for a macro, you reach the ratio 1:1 with the Sigma, not with the Canon, that needs and additional adapter...
Have a look at this Sigma.