Color matching functions (CMFs) form the foundation of colorimetric calculations. Among color-normal observers, individual differences in visual perception lead to substantial variability in CMFs. While this variability was historically less critical due to the broad spectral characteristics of most stimuli, it has become increasingly important with the growing use of narrowband spectral sources in wide-gamut displays and lighting technologies. As a result, individual observer CMFs have become an important topic of study. Li et al. introduced modifications to Asano’s Individual Colorimetric Observer Model (AICOM+), including the adoption of the 2012 CIE ocular media model and the removal of LMS normalization prior to CMF conversion. A rapid approach for estimating individual observer CMFs—a reduced model with fewer parameters—was also developed to avoid overfitting while maintaining high predictive accuracy. These individualized CMFs were previously validated using achromatic matches. In the present study, the colorimetric accuracy of the individual observer CMFs derived from both the full AICOM+ model and its reduced version was validated, using a rating-based experimental method with the same setup. Nine observers, randomly selected from the original cohort, participated. Their individual CMFs were compared to the CIE 2015 10° CMFs using the rating data. The reduced AICOM+ model yielded more accurate predictions than both the full model and the CIE 2015 10° CMFs for 7 out of 9 observers. Future work will apply recent improvements to individual observer models to evaluate potential further gains in predictive accuracy.