Not to beat a dead horse, but, Dont go Kong!
I do believe it is a favia, possibly montastrea. Favia is almost a relative term, I would also venture to say for as many favia that have been posted there are equal posts which are not favia's at all, but on the outside are virtually identical.
An ez way to ID a cyphastrea is just by sheer size, I could be wrong but the mouths on your piece probably range from a dime to nickle sizes? Where on a cyphastrea you could probably fit 4-5 mouths within the circumference of a dime.
Needless to say, Im hooked! Gorgeous colonies and pieces everyone
I'll be posting my 2 humble frags soon.
-Justin