Surely these large RAM figures for Omega point up the advantages of running RO 5 on it? With RO 3.5 to 4.x, you can only use large amounts of RAM for Dynamic Areas; the WIMP slot is stuck at around 28 MB however much RAM you fit.
That's why PACE (Castle) rejigged the memory map for RO 5 to allow WIMP slots up to 1 GB. Remember that the WIMP slot is the only address space that can be used more than once (I have the horrible feeling I'm going to be argued with on that one but the essence is correct).
And you can only grow the WIMP slot by any large amount if you run in a 32-bit processor mode (rather than a 26-bit one), so you just can't copy it in RO 4.x.