so i read that thing that said the only cons of hdpe was the cost.
my dad owns a machine shop that cuts metal and plastic into parts for medical/military/optical stuff and uses the material quite a bit. he says it isnt very expensive, i dont know what people consider expensive but:
http://www.mcmaster.com/
then just search hdpe and they tel u all about it u can choose lengthswidths everything.
hope someone finds the useful