Main difference is the blend, and the bite switch and cab sim buttons.
V1 VT Bass had none of these. The V2 has a cab sim button, but turning off the cab sim also turns off the presence boost, resulting in a darker sound than you had with the cab sim on, which is not what most people (IMHO) would want from this button. But that’s remedied in the DI version, which puts the presence boost on a separate Bite switch.
I really like the blend feature, since I dial in an obnoxious clanky overdrive sound with the character turned up fairly high, but back that off with the blend. Result is kinda like the Geddy Lee pedal, and it’s a tone you can’t get from the original without a separate blender.