Not speaking to authenticity here (just not familiar): However: very nice image with good placement and pleasing ink color (seeming to echo the guitar a bit). No sticker? :)
It is a solid genuine recent style Brian sig. Does not seem rushed and has no smearing ect. Excellent placement imo. Good color ink (maybe a silver would pop more, but it looks lovely regardless). This Brian sig is what you we call an ideal example for his hand from recent years.