want to hear your opinion - is it worth upgrade Sony 28mm f/2.0 to Batis 25mm f/2.0? Will use mostly for wedding as wide angle prime.
Depends on how you use it IMO. Stopped down with the corners thrown OOF, the 28 will work just as well as the Batis 25. Where the Batis excels is when shooting landscapes and what-not where you want edge to edge sharpness.