I would also recommend Rescue Bots. The TV show is also really good for infants too, as it's pretty well written for that age group, and manages to provide action and adventure without violence. However, as your son gets older, you may want to also consider some of the previous preschool TF lines like Go-Go-Go-Bots and Tonka's 1-2-3 Transformers (which are like the MPs of infants' TFs ).

But in my personal experience, nothing beats just role modelling playing with Transformers with your child. My daughter's spent her whole life watching me play with my Transformers with care and respect, and she does the same thing now. Initially I just let her play with more kiddy TFs like the preschool TFs, Happy Meal TFs, Bot Shots etc., but since she's started Kindy, I've let her progress onto actually playing with vintage G1s and even MPs. Never had a problem with her being too rough with any of my toys (I have more of a problem with her losing toys ).