Please tell me about using an om-d with a FD adapter and FD lenses

Hi,
I tried three FD lenses on my OM-D.

Two old ones from EXAKTA (35-85mm and 85-300mm) which were very, very soft. Stepped down to f11 still some softness.

I tried a canon newFD 200 F4 which was much better. But even stepped down to F8 it was not much better than my 14-150 at F5,6.

Next step would be a 200mm F2,8L but I think I give up and save the money and go for the Oly 75-300mm.

The adapter I bought has a ring with two positions, the "Open" position opens the aperture and the "Locked" position enables manual aperture control.

http://www.amazon.de/gp/product/B0042SQ8UM

The adapter is well made, it fits very good on FD and mFT mount. Focus to infinity works too.

I paid about 14Euros for it.