fsx-se AS16 with REX and /or ASCA

[Hoang 108]

Hi, before going further I'd like to say this is not a comparison of the graphic. Both enhance the texture enough for my taste.
I'm using AS16 now and I'd like to ask how is it different when using AS16 + REX to when using AS16 + ASCA ?

Are there any advantages when using ASCA with AS16 that REX doesn't support?
 

And, AFAIK, ASCA is only the cloud texture while REX has cloud, sky, water...?

Can all these 3 work together and does it affect the VAS a lot? (without HD textures if there are any).

 

I'm using REX soft clouds now and I think I need something...better I guess.

 

Thank you!