A paradox: The multi-platinum wonderboys of Rascal Flatts catch up with meteoric chart success on Rascal Flatts Live while nudging beyond limits imposed by it. Sudden success can be constraining, and the Daytona Beach-based Live finds guitarist Joe Don Rooney and cousins Jay DeMarcus and Gary Levox--the band's multi-instrumentalist and vocalist, respectively--occasionally (okay, very occasionally) indulging musical passions beyond the slick-and-safe country pop and frothy love-anthems that have endeared them (as a supporting act) to Alan Jackson and Toby Keith's audiences. Among other things, the trio sounds fit to burst with gospel, as suggested by DeMarcus's cameo role as vocalist on a cover of "Lean on Me." (Um, do these guys know he's a better singer than Levox?) There's even a detectable groove on "Prayin' for Daylight," and the group's blowout encore, a cover of Boston's "Long Time," suggests a healthy restlessness within Rascal Flatts' ranks.