Product review (5 stars): Well worth the money, nice timesaver, easier to install
I'm a home handyman and have also worked in a research lab.  I have set up maybe 50 lines like this, in one form or another.  And, I was ready to go through the old routine... buy a length of translucent polyethylene tubing, loose brass fittings, and go through the routine.  But, when I bought my refrigerator water filter here on Amazon, this was mentioned somewhere on the page.  It's a bit expensive compared to my old method, but it looked like it would save some time, so I went for it.

I am writing this review to tell you it was worth every penny, and then some.  Here's why:

1. The ends are already set up with the right parts, including plastic compression part.  No loose parts to chase around, totally user friendly.  This may seem trivial but if you are contorted behind a refrigerator and a part slips away from your reach, it suddenly has greater meaning.

2.  The PEX tubing handles better than poly.  By that I mean... if you draw it through your fingers to straighten it, it pretty much stays straight, where the poly will instantly recoil.  And, at the same time, the PEX that you leave coiled coils nicely, which is a nice thing when you are pushing the refrigerator back into position.  Also, the PEX is a more durable product in general.

If your time is worth any money at all, this is definitely the way to go.