Interesting to hear - my research (inspired by your troubles) led me down the same paths - found that iliac veins had high patency, but the more mobile and crushed subclavical veins have more trouble:
(If you go to that thread, you'll see that others responded to my concerns with some positive research (skip past the bickering to page 3) ... I hope it is helpful, although looking back it doesn't appear to me that the issue of long term durability of a compressed, mobile stent is addressed.)
I wish I could find better reason to hope for a future free of complications, but I guess that the fact is that this is novel territory we are entering into, and you are one of the pioneers. There is no history to give guidance - you're creating that history now ... which I know is no help or comfort - but I have faith that techniques will arise out of necessity to deal with any problems that stem from this pioneering work.
If CCSVI is indeed a causal issue to MS, there is no doubt that TONS of money will be poured into finding a way to defeat it.
Keeping stents open and functional long term - and fixing any problems that may occur with them - will be a huge part of this (given the apparent inadequacy of angioplasty for jugular stenoses). I am sure you will have many of the best and brightest minds working hard to keep your jugulars open ... good luck, and thank you.