Don't get your hopes up. They're brief, poor quality cell-phone camera vids. But they're something, at least. From YouTube:
There is also a longer poor sound recording of Aya singing Lost My Music. But if you really want to see them in action, check out the promo video for the DVD of their March concert, which has now been posted to YouTube.
Searching for "Aya Hirano", "AX SOS", "Anime Expo 2007", "AX 2007", "平野綾", "SOS Brigade Invasion", etc., on YouTube, and setting it to sort by date may turn up more things as time goes by.
Aya has finally posted something on her blog: a picture of herself during pre-rehearsal make-up, apologizing for the two-day delay in posting (very unusual for her), and saying that the concert was "under very difficult circumstances" but that they "surmounted the difficulties." I suspect Aya may have taken two days to regain her composure after the problems.
From other sources, I know that the start of the concert was delayed two hours; the video was fouled up, with the wrong videos, or even a Windows desktop, showing on-screen sometimes; the main speakers weren't powerful enough; and various sound feeds were out of sync with each other. The technical level was like a high-school festival, according to one Japanese attendee posting on 2channel.
By all accounts, the whole con was poorly run -- or at least the problems overwhelmed the planning: long lines in the sun, awkward siting, delayed and cancelled events, surly staff, aggressive security, poor communication. Momoi Halko has a long screed on her website lambasting the whole thing, but saying that the fans were wonderful and brought her to tears of joy (again). Details from Canned Dogs.
But all reports from the SOS Brigade Invasion concert are positive, despite the problems. There are some great comments from attendees posted following my previous posts about the event, and also on AnimeSuki. Thanks to you all.