ASC vs GIK?

I have GIK now, but feel they aren't doing the trick

Room acoustics is not with vibes. It is a meticulous, iterative based process buttressed by measurements. So unless you're doing all the above I'd hazard the guess is user error

Now to answer your question, I've had acquaintances who have used GIK, DIYed (which I favour if you are up to it) and have had great results 

Have to know what you are doing and how to deploy them in your room. 

I did have GIK Do a room analysis. I followed the suggestions mostly. Didn't buy as many as they suggested as I thought it was a little excessive. 

What appeals to me about ASC is they are primarily floorstanding, making them easier to move than ones that are mounted to my walls (which are starting to look like swiss cheese from all the holes),  The tube shape will take up less space and the fact that you can tune in the amount diffusion by simply turning them is also a bonus. 
Basically, other than the cost, do they have any known downsides?

My GIK products are high quality but their company is very disorganized: Poor customer support and they seem to have no standing inventory so very long lead times. I am still waiting for diffusors I ordered on December 2nd...