It was real humid at my show too. I don't know how the hell Maiden do it. They are 55 years old and they run around the stage like a bunch of 20 year olds. There were flames shooting up on stage and all this pyro in that heat, they must've been dying up there. Bruce even mentioned the heat and wrung out his shirt which was absolutely drenched in sweat.
I thought it took a few songs for Maiden to catch fire, (I'd say "Afraid to Shoot Strangers," the 4th song, was when they hit a groove), but once they found that groove, they were awesome. Alice was great too, and both Alice and Maiden had great sound. You could make out every lyric, the bass was clear, just a really great mix.
What shocked me was how the Iron Maiden fans outnumbered the Alice fans. I get Maiden is popular, but Alice is a legend. One guy behind me tried starting a "We want Maiden" chant during Alice's set and I just gave him a dirty look and admonished him for disrespecting a legend. I've been to dozens of shows and saw plenty of opening acts who deserve that treatment, myself being guilty of giving Static X the "Slayer" treatment, but Alice deserves way better.
Still, I had a great time and I'm glad you and your sons did as well.