I haven't posted much about the IR1250 since it was replaced, but I had a bit of a problem yesterday that one of the IR1200 features "fixed".
I went low during my cardio session, had to stop and eat dinner and then resume to prevent a crisis. What I should have done, was to set my temporary basal about 2 hours before the planned session.
It wasn't a problem before because my blood sugar was running too high in the afternoon, and I needed the cardio session to help bring it down.
Since I tend to work out about 4:30, I set an alarm to go off at 2:30. Then I can decide if I need the temporary basal or not.