It is interesting.. I've been doing the same with my herd, and now that I have many cows that are 7/8th sisters but from different maternal lines, as well has having 3 generations of animals, it makes it kinda fun.. Despite it's a bit of a waste for a guy with 25 head to have 2 bulls, it really changes the breeding possibilities, and it's insurance if one fails. Since I had some cows get old, I also have animals with no influence of one breed or another.. We had SH bulls for 8 years, so we have a lot of SH influenced cows, but old cows like Rosie were from the previous Saler bull, and lived through the SH years and I got two daughters with Gelbvieh but no Shorthorn. It all makes for the ability to cook up interesting combinations. I may at some point trade off Marko for my friends bull I raised (Hector, Marko's 13/16th brother) He's been producing great consistent calves for my friend.