Thanks for the reply guys. I originally ordered the 3/8" fittings but found they were excessively tight with the Norprene tubing (1/4" ID) that comes attached to the Halcyon p-valve, so I switched to the 1/4" fittings. I totally get what you're saying about restricting size, but hopefully these should work for me. They fit great with the tubing and because they are barbed, are super tight without a clamp. I'll have to wait to get home to try the fittings with the Rochester catheters I have.
As for the tubing, you are probably talking about Tygon tubing, which is very chemically resistant and would be a little more flexible than the Norprene. It also comes in clear, so it would be easier to see if it was dirty too. I'll try out the Norprene for now and look into Tygon if I have any problems. Dec 12-13 will be the big p-valve test.