In your other post I asked about frame size but as far as Tonic, I would think he wouldn't change a frame size too much. I have one due out of Tonic within the next two weeks. I did breed him to a few heifers. He is not a huge, massive bull and I think he will work on lots of different types of cattle. If your heifer is upper - moderate or large framed I would use Jake's Proud Jazz on her.
From the Tonics I have seen, if you have a really powered stout featured cow that needs alot of refining, a flatter muscle pattern and prettying up he would work there. The calves I have seen are pretty fronted but other than that they narrow based, lack muscle, bone and guts.
The heifer in my profile is an Eskimo Joe, we bred her to Tonic and had to c-section the calf. We havent got her bred back yet, a year later. I am not saying he won't work, I would be careful though. The tonic calf was a heifer, mostly red average bone and thickness. He is not going to add muscle.