What is the best place to gach?

Yea thats it. Where? I have enough NX credit to get a couple and just wanted to know where the best one is. In the past I have done mushrom shine.

In mushrom shrine, if you fail to get something really good, you get a dark scroll wich may or may not suck.

In henesys, I 've had more luck, but failing ends up in horrible items. The same goes for NLC.