Kevin,
About a month ago we ultrasounded the first group of Len 502R FR-1 Braford calves (6 months of age). We were only looking for IMF- too small for ribeye size yet. Average IMF was 5.75% and ranged from 4.73 to 6.24! This is from natural service calves. Some of the Brahman females were ones that we didn't have carcass data on so we weren't sure how he would do on them. Looks like he definitely is passing on the IMF to his calves.
We are planning to make a lot more F-1s with this great bull.
Hope you and your family are doing well. We'll try and make your next sale.
RoyLee & Angela Herbert