Maple will tend to blotch, even hard maple. I am working a small project
right now that has some maple. I treated with MinWax pre-stain conditioner
and still got a little bit of unevenness in a spot. I recommend a thorough
treatment with a pre-stain conditioner or mineral spirits before staining.
Curious - what are you building from maple that is going to be that dark
(even more critical for blotching)? Could you get by with Birch at less
cost - but probably more blotching?