This is kind of a tough question I think. First off I don't think the Wine & G.E. color are very similar. I only own a glazed espresso bag but have seen the wine color before and I don't really use my GE MAM as a brown bag. I use it when I want a little pop in my outfit because it does have the *slight* burgundy hue. Having said that I am looking at it now and some might think of it as a brown bag.
When it stands alone it looks brown but if you put the G.E bag next to another brown bag or shoes it looks different. I love this bag to death but if you are looking for a real brown bag it might night be the best. If you have several brown bags and want an addition than this might be fine. Have you thought about the Mocha? That is a lovely dark brown color!
This is just my opinion- hope it helps!