Compact binoculars are handy, but you'll be much happier with 8x40s. The little ones make it very hard to find the bird, much less the tree since the angle of view is so narrow. I bought some from REI for around $170 a couple years ago that I love, and they are not much bigger than the Minox that you show here.

Best bet is go to a store and try both sizes out and see which ones you can see the best with.