The OSBDM08 doesn't do trim like the P&E does. That is a shame but so be it.
I have checked a half dozen new 9S08QG8's and a couple of 9S08SH8's. The factory trim on the new parts seem to be quite accurate, However, when you load your program into the MPU the first thing Code Warrior does is a mass erase which removes the factory trim from NVICSTRM ($FFAF).
Anyone know a work around other than changing your source code for each different chip?