Flimsy and opaque is okay - it is normal for it to turn cloudy after boiling, and doesn't affect its function.
Since milk doesn't touch the tubing, as long as there's no visible mold growing in it, I wouldn't worry about it too much. You can boil it or microwave w/the medela microwave bags. Any bit of minerals in your water will leave a residue when the water dries, but again, not a big deal.
I got replacement tubing at breakoutbras.com
ETA: Medela has some FAQs about tubing that can answer your questions:
http://www.medelabreastfeedingus.com...mothers/tubing
Last edited by pb&j; 04-03-2010 at 02:46 PM.
mommy to DS who is 9
DD who is 6
and my girl in heaven