Pros and Cons.
 

Alright Im thinking of changing my box into FiberGlass instead of MDF(3/4)
anyways what is the Pros and Cons between the 2?

go with f/g

does F/G effect the sound?? Im also going to be porting if i go that route.

if it is thick 3/16 or over (than no )

3/8 minimum

ok
my box is about 1/2 the thicker the better

Ok So ill go about 1/2in or more but how about the inside any liners??like Dynamat or BB Whatever i need?

Rhino lining works great on the inside of a box to totally seal it.

are we talking about the same at the truck lining on the bed???? Otherwise if not post a link for me so i know which company it is.:P

If so how many layers? is good for that?

Yes the same stuff as bedliner. 1/8" is tons. It does nothing for structural intergrity of the box though. It is only to make it air and waterproof. Glassing = $, time and if you have not done it before, mistakes that you will learn from.