Objective: To define the function of the “Ross valves” and its clinical meaning in a practical valve performance classification as part of the outcome analysis. Methods: From 1994 to 2017, 630 consecutive patients underwent the subcoronary Ross procedure at our institution. The valve performance classification combines hemodynamics, symptoms, and management criteria. Median follow-up was 12.5 years (maximum 22.3 years, 7404 patient-years, 99.4% completeness). Results: The mean age of the patients was 44.7 ± 11.9 years. Hospital deaths was 0.3% (n = 2). Twenty years after the operation survival was 73.1% (95% confidence interval [CI], 65.4%-81.6%) and statistically not different from the age- and gender-matched general population; freedom from reoperation was 85.9% (95% CI, 80.2%-92.0%; 0.6% per patient-year), 89.8% (95% CI, 84.3%-95.7%) for autograft, and 91.0% (95% CI, 86.3%-96.0%) for homograft. Preoperative annulus diameter, aortic regurgitation, annulus reinforcement, sinotubular junction reinforcement, and bicuspid aortic valve type were no significant risk factors for reoperation. At 20 years the probability of a patient being in valve performance class I to IV was 5%, 74%, 19%, and 1%, respectively. Time to reoperation was not different in bicuspid and tricuspid aortic valves; preoperative aortic stenosis tended to have better outcome of autograft function. Conclusions: These up to 22 years data show that the subcoronary Ross procedure continues to provide an excellent tissue aortic valve replacement. The suggested valve performance classification emerged as a practical concept for outcome analysis with the probability of 79% being in the favorable class I or II at 20 years.