Mammillaria beneckei

I couldn't really wait until the flowers are open, although it shouldn't be long now. This is partly because I have a new toy - a camcorder - which can take fairly decent stills - so this is an example of that as well.

The plant I bought 2 years ago at ELK, and kept in over this last winter in a warmer area, before putting it back into place on the bench in March. It obviously likes that treatment....and has grown a second offset as well.

I never could my beneckei get into flower. Although I gave it the same treatment as you did. For balsaoides, no problems, this plant flowers every year.
I think that it is like M. senilis, sometimes you have a willing one and other times you haven't.

And today two of the buds are open....so I am a happy bunny...it must like the heat of these last days.