Pour able transom

[never satisfied]

I am doing mine on my 82 cuddy Outboard. So far I've taken the cap off and chainsawed the wood almost completely out. I drained the bar oil and cleaned it out. I figured I didn't want to have any oil in there that I might have to clean out later. It hasn't been hard this far. Now I am researching which brand to go with.
1. Sea cast seems really thick. I worry about what absorption I will get to any wood that I didn't get out
2. Carbon core is the ceramic from the videos looks like my favorite option. Thinner and would flow better into the tight areas.
3. 3m makes a similar one but its a little cheaper. Nida is the name.
4. Transom repair kit is the one I seen today. It is said that you only need a fraction of the amount the others are claiming. I think it is expandable but I am not sure. I've called the manufacture and am waiting a call or an email back.

Not looking for the cheapest option. Looking for the best option.
I do know I don't want to have wood thou.