I am thinking about upgrading my 14-150mm +3 Marumi achromat combo to the excellent 60mm for macro work.
Buuuut: For similar money I could upgrade to Oly 75-300 which could be quite versatile for tele and macro.
Anyhow, your coin picture inspired me to do the same with my 14-150. My lighting is not as good but sharpness is OK.
Still very undecided between 60 or 75-300. I will try it at my local photo shop, maybe comparing directly will help.