Japan has been engaged in QE for a long time. Abenomics involves more than QE. Recent experience (and older research, c.f. Krugman) shows monetary policy simply isn't going to make any real difference in situations like this. It's better than _nothing_, maybe, and might hold you steady, but that's about it.

That said I don't think Abenomics is going to be a resounding success. There's just not that much changing in terms of fiscal policy, which is the only thing that's going to have real short/medium-term impact. There's a little, and it's an improvement, but not a lot. So I'd expect to see small gains.