2mg trankimazin from P24 IS Upjohn Xanax and very good.
2mg mylan alpraz (US generic) is also very good.
2mg Gador Alplax (Mex generic from Farmakos) also very good.
Not very impressed with 1mg Alprax (Indian generic)- probably about half strength.

Someone mentioned Geneva, a US generic. I haven't had their alprazolam but I have had another benzo from them, triazolam, and it was worthless.