Looks good. I have lost through grafts(TG) that look healthy like this upon detachment--but usually, TG that looks like this are good to go and don't skip a beat. A few things I have done that may make a difference: A head of time cut all green off branch except the proper side; leave long piece of branch when you sever it, cut flush later, be sure to develop and preserve buds of new TG close to trunk but let branch tip grow unfettered in final stages, strong growth of TG assures good mending; I think spring is best severing time however one can cut everything energetic back(except TG) in late summer in preparation. I usually let sac branchlets help strengthen the new TG in the following years.