Any and all grass fed beef is not as good. That is due to it screwing up the fat profile. Grass fed as a cow naturally would be is best. 90% of the stuff in the stores is grain fed so its LOW in omega 3's and high in sats and o 6's. Go with the grass fed or eas lean as you can and supplement your fats.
Other than that it wont srew with your hormones etc. Not in a direct relation to Phyto estrogens or anything.