28-70 is a sweet little zoom lens with macro function. I have no problem with this lens and like it very much, but I must admit that I am not a zoom fan and almost all the time I am using prime lens. To me this lens has better distortion control and much more flare resistant over the 28-85.
But from I have heard many people think the 28-85 is a better lens. But it is very huge and heavy.
I used to have both and since I use so little zoom lenses I have decided to sell one of them and I sold the 28-85.
Cannot say much about Leica as I cannot afford them.
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Rolleiflex 3003, SL2000F - SONY Alpha7R 1/2/4. A1
Carl Zeiss C/Y T* - QBM HFT - ZM T* - ZF T* - Batis T* - Otus T* - Loxia T*
Sony. Zeiss 16-35/4 T* G200600 GM100400 GM600
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