What interface are you running? And do you know (it should be in the manual) the input impedance of the the instrument in? If you have a decent interface with an instrument in, you shouldn't need a DI. DIs are really important if you have a problem with your interface not having enough impedance (and giving you blocking distortion) or if you are running your guitars directly into an ADC like Protools HD192 or Apogee AD-16X.
It is very important however to have a good reamp box, as you want to return the signals output impedance to whatever the guitars pickups where if not lower. I would suggest really focusing on getting a reamp box above anything else if you want to reamp.
The redeye is a Swiss Army knife, it would be a good buy.