I'd be very interested in statistical reliability figures supporting the notion that an MCU will run better at 11.0592 MHz than at 12.000 when 12.000 is the rated maximum.

I know what you're saying, and using the 1W resistor is probably better than the 1/2 watt type, but do you really think it worth the extra cost? These are all, after all, commercial devices intended to be used at room-temperature. I worked in the aerospace/defense industry for a number of years, and, quite surprisingly was confounded by the notion that their reliability assessments claimed that running 4000-series CMOS at close to the rated limits of speed (~5 MHz)was much better than running Advanced CMOS devices rated for 180 MHz at the same speed because the circuit was operated at 5 volts, and the 5-volt AC logic was rated for 5 volts +/- 10% while the 4000-stuff was rated for 3 volts to 15 volts.

I don't see the advantage of using a 24 MHz device at <8 MHz as compared with a 12 MHz device, though I doubt anyone makes a 12 MHz device any longer.

I see you've chosen a convenient frequency for baud rate generation. Is there any reason other than that to use that rate?

RE