Saw them in Lisbon last night for the first time. My thoughts on it: technically speaking it was excellent save for the poor audio technician going back and forward all the time in the stage switching the instruments and arranging the set.
The music sounded as good if not better and more aggressive than the studio version of the albums. The lead singer ranges from "similar" to "exactly the same" in terms of imitating Gabriel's voice, but he nails it most times.
Didn't like the "obrigados" (thank yous) between songs nor the parts where they broke character. The guy playing keyboards wasn't a band member and was completely out of place clothing wise. But he was very good playing.
The initial Wind's Tail medley was amazing, particularly Blood on the Rooftops. But none were dressed in costume. The Lamb part got tremendous applause from the audience (after all, the original Genesis did two shows in Portugal back in '75 to promote it, and it is recalled as one of their most bombastic concerts). The audience sang during The Carpet Crawlers and the lead singer did some incredible jumps and moves.
Last part was amazing, and ending with The Musical Box (ft. Fox Lady) was absolutely perfect.
Overall score 7/10. Pros, the musicianship was fantastic, the Lamb part and the After the Ordeal parts got the most applause. Cons, it didn't seem like a faithful recreation of a Genesis concert for the most part (this tour's purpose is a bit of an antithesis to that, though), we didn't get to hear some fan favorites such as The Knife or Watcher of the Skies (before the encore people started shouting song names and when someone said "Supper's Ready", the guy playing Mike Rutherford pointed at his wrist. People chuckled.)
I hope I get to see them doing a proper reenactment in the future. This first experience left a good if somewhat bittersweet taste.