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Hi Paul,
I use an AO8 but my sampling is on the silly side (0.44"), if there is any improvement to seeing impacts, I would say it is quite minimal. The biggest benefit I see is as Terry has mentioned, moving glass as opposed to moving a mount to perform corrections. I have observed a major disadvantage though, it can amplify micro-lens issues by washing out the very tiny diffraction spikes at every angle. On small pixels, the wash quickly fills the wells, not to saturation, but high enough to be very obvious. At least this is what I have noticed and I have since toned down to around 2Hz. Probably totally different game for bigger pixels though. But if you're already seeing flat guide logs, and tight stars, I'm not sure if you'll see an actual improvement to the image subs, apart from slightly better FWHM, but still the same seeing impacts, with a reduced likelihood of trashed subs due to the guider/mount stuffing up for some unknown reason. AO can get a mind of its own though sometimes, especially if you haven't found the right star. It can be a little more hands on than an OAG, depending on what automation you're using, from a tuning perspective (each target is different).
Just don't expect 10Hz+ to work for every target in an image run as the AO will spend most of its time being inefficient and offering nothing over an OAG, probably worse in some instances.
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