Really like the song, the riff has a bit of a metal edge to it that I enjoy. Not a fan of the solo on this song, though. Sounds like Gilberto had no ideas.
Could also be the years of playing a bajillion notes a second wearing on him. It is pretty interesting never the less has a bit of a Garry Moore edge.
Have you listened to Fuzz Universe? He seems to have plenty of ideas there.
Though I do agree the Undertow solo isn't his best, its probably one I could have half a stab at playing!