I'm building my first pistol, a 10.5" with carbine gas system on top.  The buffer tube that KAK sells with the Shockwave kit is considerably shorter than the tube for the SB15.  Do you think I'll lose reliability when shortening the tube that much?  Picture below.

I was going to get a SB15 pistol brace for my ATF approved one handed pistol bracing needs, but I discovered the Shockwave while shopping around, and it looks like a winner.  I remember reading that shorter buffer tubes cause reliability problems, but I think I recall that the offending tubes were really, really short.  What do you guys think?

Picture stolen from a handy article at TheFirearmBlog.

http://www.thefirearmblog.com/blog/2015/04/14/pistol-brace-comparison/

KAK Shockwave tube is standard carbine/pistol length. KAK super tube is same internal length as standard carbine/pistol, adds about 1.5" to overall length.

The picture is a bit exaggerated due to angle.  

- OS

Those tubes both have the same internal length.  When people are referring to the shortened tubes they are talking about the GSE type tubes that do not use a standard carbine buffer and spring.

So the Shockwave tube isn't any shorter than the tube that I'd use with a normal carbine collapsible stock?  Perfect!  Thanks for the help guys.

Correct. It takes standard carbine length spring and buffers.

- OS