My personal prefferance is dual port rams, as it does not "bog" the cpu down

Although it must be a massive project to need more than one cpu, (unless you mean for generation of DMX)

I can decode DMX and run 8 channels of stepper motors of one 8051 running at 8Mhz (although for added saftey I run them at 16Mhz)

Regards,

Kat.