She certainly seemed to have lost a lot of her skill when she came back.
But better trained and more experienced than Emma? I doubt it. For one thing who trained her, she's most self taught because there were no other psi's around to help train her, Prof X for a time, but then he left and she made it up as she went along from there.
Emma is older, more vicious, more cunning, and has achieved more with more limited resources.