I used the hinge material supplied in the kit. After installation I did a significant pull test with no failures. Having flown another slightly smaller Extra with CA hinges for the past five years with no problems, I see no reason to use Robart hinges. Robart hinges are a great product, I just do not see a need on this particular plane. Another thought is that if you have a surface failure with something other than the type of hinge supplied, will Great Planes warranty it?