I never hear the V-Moda. And because it is a closed headphone must have a smaller soundstage. Regarding taking the prints, I think this text a page on facebook published will serve you:
"What's up with the foam thing in my teeth for ear impressions?"
Using a "bite block" is one of the most important things to get proper impressions taken, especially for a singer. Based on the position of the jaw during a live performance, the seal in the ear canal with the in ear monitor can be lost with a mouth open wide - or even a smile. As we've discussed, proper fit is essential in getting the best sound. With that said, maintaining the coupling with your canal is part of what makes your custom in-ears sound so good.
The bite block allows the impressions to be taken with the jaw opened in such a way that it re-creates the position of an open-mouthed singer. Even drummers and guitar players tend to open their mouth during a live show.
By putting the bite block in between your teeth during impression process it allows the them to be taken at the open point where most people lose the seal. This way the seal can be more evenly maintained throughout your entire performance thereby providing better sound.
It's a good idea to look at both photographs and your own reflection in the mirror with your performance positioned open jaw in "live mode" prior to having your impressions taken. This way, you'll have a better idea of how wide your jaw needs to be open to achieve your best possible your impressions.
At EAR4U Hearing Centers in South Florida, and for all manufactures based on their own requirements and specifications, we like to take impressions that go beyond the second turn/bend in the ear and fill the exterior to include the helix/concha in order to get the most accurate fit for you.
And video:
PS: If it is not possible to use a biteblok use your fingers (two fingers). I used my fingers and it worked in my case.