I can’t see how any of those would save your transom at all. It’s bolted in the same place. All the weight is in the same place. Save your trim ram maybe??? IMO if you want to take the weight/pressure from bouncing on your transom the lower unit needs to be supported by the trailer. BUT then there are those that say every bump the trailer takes gets transferred to you motor (???). Dealer told me to trim my motor up so 1/2 the weight is in front of the transom and go.
But what do I know. I have a better than basic knowledge of physics. I have only had a real boat, 16′ w/ 60 Merc, for 2 summers and only take it 2 miles to the landing. I did buy a trailer mounted support (Ve-Ve – made in USA and sturdier than the other 3 brands I looked at) for mine. And if I ever go far that is what I will use.