I'll be interested to see if this manages to go off, but my best actual prediction.. neither Samurai nor Soulknife have much in the way of relevant class features. Therefore, especially at higher levels, I expect these fights will be determined almost entirely by the equipment and feat choices of the combatants. I also suspect they're likely to look quite similar in that respect, since they both want roughly the same things out of their equipment. Soulknife's main feature may give him an edge there, in that the mindblade potentially frees up a significant amount of money.

For the record, I think Samurai is just that little bit worse off than Soulknife, and I'd be willing to attempt to provide a Soulknife of up to level 5 to compete in that level range.