berg,

missing a word on the 11x8mm PVC tubes. could this be a good compromise having the advantages of both worlds:
  • 8mm ID
  • 1.5mm wall size, which gives a bit more stability
  • cheap and more flexible than PUR

what's your opinion on this one?

i use this tube size for about 6 month now and had no problems with leaking so far. although i don't use any sort of quick-fit or push-fit fittings. using the standard thread type fittings here.

anyway, interesting post!