I have used the CTI2 customs for several years doing motocross for preventative reasons and I loved them, even if they were a bit wide and ate themselves through many pair of pants.
I always used the under sleeve and had no problems with it sliding down.
have not used them for kiting since I don't feel like I need them..
For custom braces I have heard good things about the DonJoy Defiance III as well..
For off the shelf braces I would recommend you to have a look at the EVS Axis pro: http://evs-sports.com/store/product.php ... 287&page=1
And the pod K700: http://www.podmx.com/products/
The use and application between MX and kiting is quite similar and the patella cups can be removed safely for kiting.
The only bad thing about custom braces is::COST:: My Cti2's cost me 1500 for each back in the days and the custom paint job was on top of that.
Off the shelf braces are getting much better every year and you have a lot of good options. try some.
For a serious study on the effects of knee braces check out this pdf: http://cdn.thumpertalk.com/uploads/medi ... _4_111.pdf