I still have a problem with Spartan IIIs being on Reach at all. Because there were plenty of Spartan IIs (All of them basically) on Reach for the defense. Another problem is that just about every Spartan III that was of age to help fight during reach would have been wiped out in that covvie assault mission, and all of the Spartan IIIs beta edition WERE still on Onyx AFTER Reach because Dr. H showed up and found them.
I also really don't like that there are Mark V variants (Like the Mark VI and the SPI shouldn't have them either) because the whole point of the spartan programs (all of them) were A) Unity of a team, B) interchangeability of parts doesn't lend itself to unique armors.