A few nice folks on here gave me some advise this past year. We used on both our sons steers this year with no problems (besides the one not liking us messing with his ears!) Anyhow, really not sure still if they really needed it they were pretty big already. Think it really should be decided steer to steer and what show you're shooting for. That said I did both and think it did probably firm them up a bit especially this last one. Don't think it added height either. But probably varies depending again on the animal (and the type of implant).
We used the REVALOR S (not sure of spelling) Did not change ours temperament at all. GOOD LUCK