We recently saw I-67 at Ohio Beef Expo. He look like he did in his promotional picture. He is pretty stout and thick. He has thrown some nice heifer prospects.
Monopoly Money, Gold Rush, MAB all three have seen calves with added bone and muscle. We are feeding a Gold Rush that is hairy as an ox and monster bone. They have extra grow to them for sure.
I like the Unstoppable's although not monster boned they are soft made with that easy feeding look. The females look like they woudl make nice replacements. The steers we are feeding have done well and seem to get better with age.
We have a BPSL Boomer son that when used on feminine females he throws very masculine calves and heifers are very eye appealing. Purbred maine on a few clubbier cows and some registered shorthorns and maines.We used him on a high percentage maine female with a tick of clubby breeding and got a freak of calf. Dirty Harry has worked well in our herd. Double Vision(defects) but makes nice terminal animals. FSF Assisin, Phildon Fringe are a couple others but as with any of the bulls have to count on defects. defects in terminal animal may not matter but if you retain a female for breeding makes those matings that much more difficult.
I think when you said you are "just starting out" you should use bulls with options. One' that will leave you with a repalcement female should the mating not work out. Your a young breeder, start out right. I tried the popular matings etc and had large vet bills and ended up with poor milking mothers etc. Its cheaper if you are diligent in your selection process and plan for the potential replacements now.