G0704 Purchase Advice

Ok, I am about to order a G0704 and wanted some advice on what all to get to build a really nice mill.

Items to Purchase
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1 - G0704
1 - Bdtools CNC Kit w/ screws or CNC Fusion Kit w/screws
2 - 570 Steppers, 1 - 906 Stepper
3 - Drivers, keiling Digital and Acc.
? - Over size ball screw balls, what size?
1 - Hoss DVD, almost forgot this one.

Questions
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1. Which CNC Kit is better, the BDtools or CNC Fusion?

2. What mods are a must? I plan on belt Drive, motor, PDB for sure.