Resilient channel or mass-loaded vinyl for a shared wall?

I’m planning to improve a shared interior wall where voices and television noise are carrying between rooms. I’m comparing two assemblies:

- Resilient channel, followed by an additional layer of drywall
- Mass-loaded vinyl installed behind new drywall

The main goal is reducing airborne speech and TV sound without losing more room space than necessary. I’m not sure which approach makes more sense because the existing wall details will probably matter as much as the material itself.

Before choosing, I’m trying to confirm:

1. Is the wall framed with wood studs or metal studs?
2. Is the noise mainly voices and television, or is there also impact noise, bass, or vibration?
3. Do electrical outlets, switches, doors, the ceiling, or the floor connect directly between the two rooms?
4. How much additional wall thickness is available?
5. Would removing the existing drywall be practical, or would the new assembly need to go over it?

My understanding is that resilient channel can help by decoupling the new drywall from the framing, but it has to be installed carefully so screws don’t bridge into the studs. Mass-loaded vinyl adds mass, though I’m unsure whether it provides enough benefit by itself when installed behind new drywall.

For a typical shared wall, would you favor resilient channel with one or two layers of drywall, or mass-loaded vinyl behind new drywall? I’d also appreciate advice on flanking paths, especially around outlets and where the wall meets the ceiling and adjoining floors.