The purpose of the present study was to compare the cognitive and perceptual aberration scales from the Five-Factor Schizotypal Inventory (FFSI; Edmundson, Lynam, Miller, Gore, & Widiger, 2011) and the Personality Inventory for DSM-5 (Krueger, Derringer, Markon, Watson, & Skodol,, 2012), as well as to address more generally the validity of the FFSI as a measure of both schizotypal personality traits and the FFM. Two independent samples were obtained, including 259 college students (55 of whom were preselected with elevated scores on a measure of schizotypal personality disorder [STPD]) and 346 adult MTurk participants (43% of whom had been or were currently in mental health treatment). Administered were the FFSI, the PID-5 Psychoticism scales, and alternative measures of general personality, openness, STPD, and schizotypal cognitive-perceptual aberrations. The results of the study are discussed with respect to the validity of the FFSI and PID-5 schizotypal cognitive and perception scales.