Using multiple Anti-Aliasing Effects at once

First of all:
1. I don't want to use TAA for the time being. (For one it makes me very dizzy)
2. I'm using Unity PPv1 with Unity 2017.4.18.
3. The target platform is PC
That said...

I was experimenting with different configurations of Anti-Aliasing to get the best possible results.
I came up with one solution, involving three simultaneous AAs:

1. Unity legacy AA using FXAA1 Preset A
2. The Unity FXAA as part of their post-processing stack
3. Unity legacy AA using SSAA.

So there's three simultaneous AA going on on the camera. This produces the best visuals for me.
Using only the Unity FXAA is just not sufficient.
Performance wise, it's costing about 6-8 FPS.
But I'm going to have an options for the player to control the quality.

Is there any issues involved with using multiple AA like this that I'm overlooking?
Does anyone else try to use multiple AAs simultaneously?
Is it possible this configuration could be on par with the performace of TAA?
Am I being stupid trying to do this, or is this reasonable?

Thanks.

 

Can someone please move this thread to the Image Effects forum?
https://forum.unity.com/forums/image-effects.96/