Maya's Booleans are really strange...

You should read the complete Maya Online Help about Booleans, there are many tips...

I'm using them too - frequently and i think if you know how booleans work, you know why your geometry gets killed.

So... some tips:

Booleans are fully mathematical, so be prepared to loose geometry if you are modelling in too small dimensions... if my bools fail i scale both objects to 10x to try it in a larger dimension. this is caused by floating point operations. So if you try to bool to small areas, the position of vertices may float to 0 and your geometry is lost

dont bool unless you are moving and scaling in at least 0.1 steps because it leads to floats floating to 0.

but as said before... always try other moethods first - if you can do it without booleans, do it that way.


dirty trick:
if you need a boolean AND (addition) and cant do without it... try combine... ;-) but dont tell anyone