I’ve owned a VT Bass DI and currently own the NeuralDSP Darkglass B7K/VMT Ultra sim (which sounds, as far as I can tell, exactly like the pedals).
I would say they are both great - seriously great - but I wouldn’t call the VT Bass DI better. The VMT is pretty tonally versatile - the switches really change the character of the distortion. And for the distortion aspect I do like it better.
But these are two seriously top tier preamps. Two of the three best I have used (along with the EBS ValveDrive).