I have rx'd very good support from:

Mike Quarles * mike.quarles@dalsemi.com
Applications Engineer, Microcontroller Products
Phone +1-678-455-0980 * Fax +1-678-455-0921

Also remember that due to feature enhancements to the DPTR and other integrated devices you analysis regarding 50MIPS may change when you specifically "place your requirement" in context to a specific part such as the '420.

regards,
p