Aside from the first one**, I personally dont think these are among the best Ive seen.
The second looks like his head on a Sean Cody model and its decent, but it doesnt look enough like Chris' shirtless body to me.
The third and fourth just feel off to me.
And the last doesnt look realistic to me. His heas doesnt look like it belongs on that body.
But my opinion on the photos is only mine.
That you like them is cool and Im not gonna tell you you need to have better standards or that there are better photos out there. Bc you have your reasons and your standards for what a good Chris Hemsworth photoshop looks like and thats valid and perfectly fine.
**the first is great, tho IMO it would be improved with a view of his cock.