sony scd-1 versus 9000es

have modded vsei scd-1(stage 2) modded-is the stage 4 9000es better than the scd-1 stage 4 mod?
What is the 4.5 upgrade?Everyone that I have spoken to likes the modded 9000 better than the scd-1.I agree that the build quality on the scd is Porsche-like.I had the Linn karik previously-and the stock scd was much flatter sounding and nasal compared to the Linn.The stage 2 modded was much better than the Linn.Slowhand-can you give me any of the sonic characteristics of the upgrade?
I have not heard the 4.5 upgrade. In speaking with Allen Wright, he says that the scd-1 with the 4.5upgrade gives the player much more resolution. More air and space between the instruments, along with more depth. I have a friend that has the dac6/emm setup. Allan told me that I should compare my scd-1 with his setup when I have the 4.5 upgrade done. He is not saying that the scd-1 will sound better, but he feels it would come pretty close. For $400 to $500 investment, that sounds pretty good to me. Allen posts on Audio Asylum. If you go onto the sacd board, you can ask him about it.