What kind of 1/4" Copper tubing?

[hendecp]

Hey experts out there, I am wondering what the best copper is to use for winding a coil for my boka. I wound one around an 1" pipe, then back on itself. It isn't pretty, but it does flow. It tended flatten out a bit, but not pinched or kinked. Like I said, it works, but I have seen much better. I did read the thread on winding a coil and his came out much better than mine..... Ok, it was pretty damn perfect. What I got at the local hardware super store was 1/4" for refrigerator water line. Is there something better that is not as susceptible to flattening or kinking? I did my roll with out salt or any of BS that I have read all over. Mine condenses enough to make distilled water at 212. I just want to make the "perfect" coil for the best surface area and cooling of the vapor.

Thanks in advance!