Of the 2 scopes that you have mentioned, with the 7m-08, I would go with the Zeiss. I have both and really like both. But I dont know why you would need the 50mm lense for a medium caliber (I have a 7m-08 also). I would probably take my Zeiss over the 4200, but others will differ with me. Aint shopping for scopes fun?
long