There are versions of the vq in japan, vq30de-t stuff like that, the differences and demand just aren't worth importing them. Why do you wanna swap in a de-k? you could save money and labor by putting de-k intake manifolds and fuel rail on a regular de. The only other real difference in the motors are the cooling passages inside the block. Oh yeh and NAD wants 450 for the vq25, it would be a pointless swap though.