reflash or buy a N9
I had trust issues with my N900 before, but after Pr1.3 I was mostly satisfied with it, never missing alarm, mails or sms.
Sometimes I still missed calls because the phone would be changing five times its orientation when taking it out of the pocket, but by fixing the phone app to portrait it went much better.

rebooting every week-end helped a bit. At the end I had KP + CSSU, slightly OC, and it was acceptably trustable, except for the camera.