I'm not sure if the material quality has gone downhill or if our sheer volume of dust (business/production) has increased enough that we're just wearing stuff out, but we are replacing our flex hoses a lot more than we used to.
I have hoses attached to tablesaws (ripping plywood and 4/4 lumber) that get only a couple hours of use each day, and after 6 months there are holes worn through the webbing between the wire ribs....... and it's not because of sharp turns (we don't bend our flex hose like that). I don't think it's because of excessive flow/force either because this particular saw has somewhat less airflow than I used to have on it. And this saw rarely gets any melamine or laminate cut (ie, particles aren't harsh abrasives).
Same thing on our CNC. The table is only a 4X8, and the flex hose going from the dust header to the spindle is 6" hose. We used to get YEARS out of that piece, now we maybe get a few months before it's cracked and split.
I've been buying from places that sell dust collector equipment, like Oneida, and I'm pretty sure most of it is PVC.
Should I be looking into polyurethane hose instead? I'm just shocked at the price I see on polyurethane hose, it's not uncommon to see $200-300 for a 25ft length of 4" duct.