Anastrozole vs Exemastane

Is there any problem with using Exemastane (i.e. Aromasin) to control estrogen rather than Anastrozole (i.e. Arimidex)?

I read on one site that Exemastane suppresses 85% of estrogen, but they didn’t specify the dosing. Is 10 mg ED of Exemastane roughly equivalent to .25 mg ED of Anastrozole?

Also, I read one place that Anastrozole and Nolvadex should not be taken together. However, I haven’t been able to confirm this drug interaction from either drug manufacturer’s web site. Is it true? Any idea why it’s said to be okay to take Exemastane and Nolvadex simultaneously?

Thank you

www.mesomorphosis.com/articles/anthony-roberts/
aromasin-exemestane.htm

This article should explain it.