Theme of really cool bird is a satisfying map to play. The beats match really well to the song:
Not only are all of the notes are on rhythm, the pattern design reflects the melody really appropriately as well. Those two factors combine to create a satisfying flow once you've learned the map.
A few nitpicks I have with this already great map is that the first and the second half are exactly the same, save for perhaps a few wall placements. I believe some creativity could go into creating interesting variations between the two halves. On the other hand, the length of the song is perfect for replayability: it's lengthy enough to be satisfying, yet it is not so long as to bore you, or make you dread a play-through.
Readability is hindered at one or two spots due to eye-level height blocks, but that's pretty much to be expected in an expert level map such as this one.
All in all, this is a great map to play. It can be difficult, but never feels like it was made to be artificially hard, or unfair. The challenge comes from the melody of the song, as such, the difficulty feels totally organic. The hardest aspect of this song is just in reading and reacting to the notes as they come, rather than how quickly you can move your arms, which, to me, is the "good" kind of difficult.
If you're like me and value songs that challenge your mental dexterity more than your physical dexterity, give this one a try.