are Bell "fusion-in-mould" helmets stronger than the cheap models?

I was extremely disappointed with a Bell Havoc helmet I bought. Shell was extremely brittle and
fragile. I see that the "Aggressor" and other more expensive models have a shell bonded to the
styrofoam liner, which intuitively would be less prone to cracking.

Any experience with "fusion-in-mould" compared to non-bonded shells? Is it worth 2.5X the price?

(I would expect some other advantages, such as better harness or pads)

Speaking of fit pads, I find these rot within a few months and become useless. Is there a better
solution? I was consideringa Gyro "Torrent" model, which has a harness like a hard hat, but I've
read that these don't work very well (tight enough to make any difference = uncomfortable).

thanks.