IOR had some trouble with quality control a few years ago. My understanding is that the new models have been corrected. I have a 4.5x14 and it is a great scope. Tracks perfect and the glass is similar to Swarovski or Zeiss.
I have had a number of IOR scopes over the years, and have never had any trouble with them,would not hesitate recommending them great glass ,track and return to zero just smegging great scopes all round.