Most of the ultrasound-using doctors that I've talked to in med school seem to agree with you; if there's a real need for 3D imaging today, doctors (in 1st world countries at least) send the patient for a CT. The cost/benefit for 3D ultrasound doesn't compare favorably to CT because it is a much noisier imaging process and it takes just about as long as a CT.

That's why if you Google image search for "3D ultrasound", you get mostly pictures of fetus faces and very few medical conditions.

So, I see this product mostly benefitting the 3rd world, unless they vastly improve image quality and lowered the technical hurdles compared to existing ultrasound equipment. (Which would be awesome, but is a hard problem.)

Disclaimer: have used the Vscan as a student, but am no means an expert in ultrasound.