You could look at it that way, but you might be missing the point.
The REDDI is a DI box. That is all it was ever meant to be. You use it wherever a DI box is useful. It also sounds a lot like a clean tube amp. Not a cranked SVT dirt, no grind, just warm smooth "improved" fat cleanness.
The VT is an effect that is intended to emulate an SVT amp, and most of its settings are in the dirty range, from a little driven to a lot. It can be run clean, but that's not its main strength. The deluxe model also includes a DI.
If you like clean tube amp tones, and you need a DI (going to a mixer, either PA or recording), then the REDDI is a better choice than the VT.
If you want more exaggerated (really noticeable) tubey drive, fur, raunchiness, the VT will deliver and the REDDI will not.
If you do not need a DI, and all you want is an effect to go between your bass and amp, the VT will deliver and the REDDI will not.
If you want any EQ control, the VT will deliver, and the REDDI will not.
But again, there is a specific limited set of cases where the REDDI will deliver better than the VT.