Scalable video coding is emerging as an efficient alternative to simulcast encoding to distribute the same video content si- multaneously to many users having different terminals and network conditions. In order to select the best combination of video scalability options for a given network condition and content, the availability of objective metrics that can reliably predict the video quality of scalable video sequence is crucial. In this paper, we propose a performance evaluation study of a set of state of the art Full-Reference and No-Reference met- rics, considering a public database of test video sequences and related subjective quality annotations. The results demon- strate that most of the considered metrics show lack of ro- bustness as predictors of subjective quality when both spatial and temporal quality distortions occur.