The o-ring size is #9, thickness is 3/32". Yeah if I did have so much already invested in fittings, specifically QD's, I would have switched tubing out and used the fittings that came with it. Speaking of the enclosed fittings, I do find it interesting that if you buy the res from Jab-tech you get a total of 8 fittings included, but if you buy it from Frozencpu or Primochill directly they only give you 4 fittings, at least that is what their website states.

As far as the bleeding goes, I was trying to emphasize that it was hard due to the size of my case and most will not have this issue. My GPU water blocks alone weigh about 6lbs each, so my case with components is much heavier than the usual case. For most folks, bleeding should not be an issue.

And again, I want state that I am impressed with the res and the performance and am happy with the results. For me, performance trumps the minor issues I ran into, but I did want to mention them, even though they were minor.