The second one is much better than the first comp-wise and IQ-wise. In the first the warbler is just much too close to the top to make it an effective comp. The larger crop also magnified the noise (which should be really minimal at ISO 250 - is this a large crop?) Even with the better comp on the second, I still think the subject should be lower in the frame. I do like the colours, light, and singing pose. The warbler looks to have been higher up than ideal - warblers do love it up there eh!