Last year we only bred a few heifers and cows to TC Thunder, and sold some of them. We ended up with only 1 Thunder calf, a bull. In the past year I have had conversations with at least three different Select Sires employees about the bull. None of them spoke real highly on the bull. In general, he sires good footed, slick-haired, moderate cattle and the daughters have nice teats and udders. However, many of his calves apparently lack power, don't have as much performance as calves out of other calving-ease bulls, and his carcass numbers aren't as sexy as several of the other bulls in the Select Sires lineup.
However, I still think the bull is a real solid bull to use on heifers for calving ease, and if you are striving to produce moderate framed replacement females.