In my experience, that's also been true of 12.3(8)JA, save for a small number of units that have been acting up (the one we're discussing here that failed only recently, and a couple of others that have been acting up since before the upgrade to 12.3(8)JA).
No, I'm more interested in running the same version across all our access points. Only when it becomes necessary to upgrade (due to serious bugs, or specific new features, or as I did earlier this year, to bring all our units up to the same version) do I start looking at upgrading to the most current version (or ${most_current}-1, if ${most_current} hasn't been around long enough to get a bit of a shakedown).
You're probably right. We've started discussing replacing that unit with a newer (AP1200) one. That's very likely what I'll do.