The CA flex hinges work fine for just about all of the planes. But with a 3D type of plane where the control surfaces can move almost 180 degrees in travel, the CA hinges are not very good. There is too much flexing with the control surfaces in the 3D planes, so you do not want to use the CA flex hinges on those planes. In the more regular planes where the control surfaces do not move much more than 90 degrees of travel, then the CA flex hinges work great.  The CA flex hinges are about all I use anymore. Except in those certain 3D planes as noted.