ICS is about as stable as GB these days, the main difference being the battery life. ICS drains the battery faster than GB, especially with wifi or mobile data on. JB and higher, the battery life drops even further -- an hour with mobile data on, and I lose 10-15% or more battery. JB also has the occasional bug. The latest KitKat test builds seem more stable than JB, imho, but again, battery (though it seems to do better than JB).
Sent from the moon.