Mamm pollination

Hey guys!

It's definitely spring time, nearly all my cacti are either in bloom or beginning to.
Would like to know if anyone has experience with pollinating mamms?
There were a few with open flowers this morning so I took to them with a paint brush and with no prior planning dipped and mixed, wondering if they are a self pollinating and was this a futile effort?
There a quite a few other cacti getting ready to flower and I intend on taking an utterly random approach and hoping for the best!

Can post specific names if that might help?

From my understanding many of the mams are self sterile. There is a sterile/fertile list here.

http://lapsyserre.free.fr/psy_liste/SPSY2K4.doc

Thanks sneaky,
Tried to have a read of that but I can't make sense of it.
Guess I will just have to wait and see what happens, bound to fluke one or two results I hope!

Yeah most of it is in French except the species names (obviously). Read through until you find the species you are looking for then beside it will be an s or f. The S stands for "self sterile" and the F is for self fertile.

In the mammillaria section the author seems to have broken it up into multiple groups.