2x4 panel bass traps vs corner bass traps?

So in short, my room is 9ft long by 8ft wide and 7ft tall. My dilemma here is as follows:

My plan is to either A. build floor to ceiling corner traps using 15inch wide roxul safe n sound.

or b. 4inch thick 2x4 panels straddling the corners using OC 703 or Knauf.



My question is, is one going to be more effective than another? I am trying to keep costs down so 24inch corner traps floor to ceiling is outta the question. I understand that(at least it seems to me) 15inch wide corner traps seem pretty small.

Will putting 2x4 panels @4inches thick work better than the corner traps? Its a wider coverage area but obviously not floor to ceiling.


I also have a side question. My plan for the corner traps was to just cut the triangles, stack em, and wrap weed matting(very transparent material) around them. So I can slide them around if I need too. 1. Is that safe? Do I run any risk of inhaling fibers like that? And 2, can anyone recommend maybe a good adhesive or tape or something I could use to "glue" each triangle together so at almost 7ft tall it acts as one piece and doesn't collapse when I move it around.