OKI ARM7 microcontrollers are available for quite a long time, but as most Japanese vendors they are focused on the big customers and ignore the mass market. Hopefully after the Philips' success with the LPC2000 family OKI will change their policy. ML67Q5xxx is among the small number of ARM7s with build-in SDRAM controller which open up possibilities for large amount of RAM to be add to the designs and to allow RTOS and ucLinux porting.
PLUS:
Fast core runs at up to 60Mhz.
Build in SDRAM controllers, DMA and cache memory which speeds-up code execution.
MINUS:
No code protection to internal Flash.
On our boards the internal oscillator doesn't works reliable and need external
oscillator - all other designs we have saw also use external oscillators.