hi,
I know 11.0592 is the best for serial comm

Not only. You know, 11.059200, 18.432000 etc are not "magic numbers". These numbers contain some x2, x3 and x5 multipliers and so such oscillators allow you to make wide range of frequences with internal timers. For example, try to create an internal timer with 300Hz frequence using 12MHz: no way to obtain it with accurate result.

Regards,
Oleg