By 1999 The Chemical Brothers still had a few more good years left in them before their sound would noticeably spiral down hill into a more commercial EDM pit. A heavy portion of the album is instrumental. With the exception of some words of repetition on songs like Music: Response, and Got Glint. Other actual vocals are attributed to Bernard Sumner of New Order on Out Of Control, Noel Gallagher of Oasis on Let Forever Be, Hope Sandoval on Asleep From Day, and Jonathan Donahue on Dream On.
While sure you may be able to call this album Big Beat the amount Techno (Hey Boy Hey Girl) and House (Under The Influence) direct, as well make the record more diverse. This isn't the point at which The Chemical Brothers would become derivatives of themselves on most album cuts. As a matter of fact there is so much uniqueness to each track here that flow from song to song is seamless and attention keeping.
This doesn't mean some tracks aren't greater than others. The aggressive saw leads on Orange Wedge become quite stale in the mix after a while. Thankfully the track is only just over three minutes long. But these are the kind of bumps that you should expect going into almost any EDM record. Surrender is quite progressive and advanced. I think The Sunshine Underground could uphold that statement alone. But what I will say is that The Chemical Brothers like so many other EDM artists aren't for everybody. Most people like to stay within certain sub genres of Electronic Dance Music. So I would advise if you're a fan of Orbital or Underworld you may find this to be much to bright, especially in terms of the mixing. But if you like stuff like the CJ Bolland or Hardfloor you may find this to be more accessible listening to satisfy your EDM urges.