The aas community is divided on which is "better" because some guys experience undesirable sides on one but not the other, or both, or neither lol. I'd choose one and if you're experience isn't pleasant, try the other next go around. They both get the job done though
I always prefer clomid over nolva... You are going to get a different answer from everyone on this bro... Clomid has shown to be the most effective to me...