Just copy pasted from my worklog, but it answers your question. Get black (and now grey!) from furryletters 1/8" for small 1/4" for sata, and your accents (if needed) from MDPC. Also the S+H from mdpc has been cut by like 50% in the last month or so.
UPDATE: Sleeving FC6 Leads
So as I said in the first post I've spent a lot on sleeving over the past few months, since I was reluctant to pay the premium for MDPC sleeve. So much so that I've had to get a bin to store all the sleeve in:
The only good sleeve I did find in my frenzy of clicking the submit order button were "Clean Cut Sleeve" on eBay from the seller FURRYLETTERS. That stuff is great. But I did eventually break down and order some MDPC sleeve. I did this for two reasons. The first was to see what sizes "small" sleeve and "sata" sleeve were. The second was because I could never find clean cut sleeve in anything but black. Well now that I have the sleeve in my hands I can show you it next to clean cut sleeve.
Want to take a guess as to which is which? I couldn't notice a difference either. The only way I was able to differentiate is that the MDPC sleeve was secured by a black zip tie and FURRYLETTERS secures her stuff with a white one.
Here is the fan controller leads I've made using 1/8" clean cut and some SATA cables sleeved in 1/4" clean cut. Since I couldn't notice a difference between MDPC sleeve and the clean cut stuff I went ahead and used clean cut for the fan controller leads, since I got 100' of it for like $16 shipped. I hope Nils won't mind my post here, I won't post it anywhere else, so as not to give it too much exposure. If Nils wants me to take it down I will. I understand that this may be some secret sauce which is kind of like intellectual property in that it is perhaps a trade secret.
Two tips I would have for beginners are first, when you have the cable sleeved and the two pieces of heatshrink on and ready to go, don't jump the gun. Put the connector back on first so that the heatshrink can be slid down accordingly. Second, stretch out the sleeve to it's limit before tightening the heatshrink. Apparently that "closes the weave structure." I only learned both today, so the SATA cables weren't done using the latter method.