MPC 1000 questions

I am considering purchasing a MPC 1000 but I have a few questions that hopefully you experts can answer before I do. First off, is there any difference between the blue one and the all black one other than there color? Also, the hard drive conversion that is now available... with that installed does that replace the need for the memory cards? Lastly, what is the maximum amount of internal RAM will these things take? Thanks in advance for helping me out.

Thanks,
Kevin

is there any difference between the blue one and the all black one other than there color?
This has been discussed many times before, please do a search.

with that installed does that replace the need for the memory cards?
This has been discussed many times before, please do a search. No, 2 different purposes.

Lastly, what is the maximum amount of internal RAM will these things take?
It's in the manual.