Questions about legacy Zuiko macro lenses and OM-M43 adapters...

I really want to get back to nature with my new OM-D.  Kicking myself for selling off all my old legacy OM macro lenses. Seemed at the time someone told me that, since they were not 'optimized' for digital, I would be better off image quality-wise with newer "Digital" lenses.

Is this still regarded as true?

I am on the precipice of reacquiring my 90/2, 135/4.5, 180/2.8 and maybe even the 300/f.5. The last three of these I used to good effect with the telescopic auto tube. Can I expect good results with these older lenses?

What happens to the overall "functionality" of these legacies when you add the extra length of the MF-2 Zuiko to M43 adapter? I assume they work OK in A mode, but are their any other caveats?

Thanks!

CG