Ranking of quietness:
1) Romer-G Linear
2) Romer-G Tactile
3) GX Blue
That would also be the same ranking in terms of actuation force (from least force required to most). I haven't had trouble myself with the minimal experience I had with the Linear switches, but there have been users reporting accidentally hitting other keys as they're typing using the Linear switches; there are "less" accidents using the Tactile switches, relatively speaking.
The Linear is the "quietest" while also feeling the "mushiest". Think of 'em kinda feeling almost like membrane key switches?
If you're more familiar with Cherry MX switches, then the closest comparison I could make would be like:
- Romer-G Linear = Cherry MX Red
- Romer-G Tactile = Cherry MX Brown
- GX Blue = Cherry MX Blue
They're not exactly the same, but it's close enough that it should give you a rough idea on how each key switch feels.