An update to this thread: we have tested the Saramonic, but the conditions at those selected gigs were not satisfactory enough for us to give an informed opinion and publish decent clips - we're still working on that. The problem with using the Saramonic is the incredible faff with setting up the tripod, the camera, the Saramonic itself, attaching microphone supports, plugging in cables and microphones, and placing the whole caboodle in the best position to take advantage of its capabilities. We only use it at one gig every 6 or 7.
As a further update, I have now bought a Zoom Q2n to use alongside the Saramonic (or the Canon SX40, which is still going strong), not as a replacement but as an addition, to allow us to film from a different angle and capture, say, the whole of the room including the audience, as opposed to focussing on the band and occasionally turning the camera 180 degrees. So far, I have mixed feelings. My 'interim' review on Amazon, where I bought it, explains:
We'll be testing it again this weekend.