FaisalAlroqi wrote:

Thank you. I lean to dvarw fl dl but it's loud and noisy rta. is the other 2 same loud or smooth?

I have a 24mm Dvarw DL FL with a 2mm airflow option. It is very quiet. I have an authentic Kayfun V5 as well as 2 SXK clones I keep for parts. At the most open airflow setting, there’s barely any sound. Scylla and Avatar are both very quiet I the largest airflow setting.
But considering noise and whistling could also be related to the build and the space your build occupies inside the RTA, the silence of my RTA’s may not be the same with yours.