I equally like them First one has really good lighting but needs better blending of the render. He seems to have a black outline in some places. Perhas add some more colour around him to mask it up (and additionally to create flow) As for the second one, the blending is good there since you have a darker bg but the lighting could be more present. You can see the render is under influence to heavy lighting to the right (on his face) so a more prominent light source is needed.
im liking the second one most but i think it may be too dark to the point where its looking blue on his face, keep up the good work, good luck with these
