I <3 my high tec c's in my pen type a. Also have another pen body for hi tec c but i forgot the name i believe its made by karas kustoms.
Yea, I saw all these really nice looking hightec C pen holders on Kick starter.. However, after getting one, I realized that part of what I love about the Hi-tec C is how "Light" it was.
Now that I attached a heavy steel tube to it, it looks AWESOME, and a possibly handy in combat... But,, the magic behind the pen is lessened by the weight... It made a great gift for a heavy pen lover friend of mine though. 
I am now looking for an Aluminum tube/holder perhaps, but, I've yet to see one come up..
Perhaps the tube wouldn't be very durable because it can't quite be that thick.
Dream would be a "resin" holder.
what one did you get?
the one on jetpens

, where else.. pentypeA
But yea, I think alot of people who also bought it are deluding themselves as to the "usefulness" of the holder.
First off, it's HEAVY, so you would NEVER want to carry this thing around...
it's quite slippery, because the steel is very smooth... poor grip unless you have sweaty hands, which I lack

Hi tec C is quite a "thin" tip "usually", which means the pen will be somewhat scratchy no matter what. now with the plastic regular barrel this isn't a problem because you hand only has to overcome the weight of the scratchiness...
Now, with the heavy barrel, you have to overcome the momentum which results from the scratchiness x10...
It's a well machined piece of decoration at best...
This is just my opinion...