Most definately true. Ohxf333 causes fast production but not good pears. Give it 2 or 3 more years the roots will catch up and the flavor and size of pears will improve. I cant even eat some ohxf333 fruit the first years. I normally dont even pick them. The roots on ohxf333 are inferior to every other pear i grow. Callery and BET rootstocks shine greatest during a drought. My neighbors that use ohxf rootstocks wont even get pears and yet my callery pears were still covered. Callery have massive roots that have more access to nutrients. That is not to say they uptake all of the nutrients but that is a seperate conversation.
So everything is great about callery rootstock right? Unfortunately no, they can be invasive and are given to cause overproduction which leads to small or less flavorful fruit at times