The funny thing about Trujillo is that he doesn't even switch companies... because he doesn't have to. The fact that he's with Metallica allows him to cross out any kind of "exclusivity clause" that might be contained within an artist endorsement contract.
The one credit that I can give him is that he actually plays most of it live in each show... here's the
live equipment list from their last tour:
Warwick 5 string Trujillo chrome
Warwick 5 string Trujillo heavy chrome
Warwick 5 string Trujillo "Terminator" black chrome
Warwick 5 string matrix turquoise
Warwick 4 string Trujillo blue chrome
Warwick 5 string Trujillo blue stain maple "Surf Stringers"
Warwick 5 string Trujillo black stain
ESP 5 string Trujillo model army green Nash
ESP 5 string Trujillo model Dirty Donny
ESP 5 string Trujillo Red Scorched
Tobias 5 string "Aztec de la Chloe"
Tobias 5 String blue stain
Tobias 5 String black stain
Nash 4 String P-Bass white w/ red tortoise pick guard
Nash 4 String P-Bass "Jailbreak" black
Nash 4 string P-Bass 62 Black w/ copper pick guard
Nash 4 String P-Bass yellow "Shitblaster"
Nash 4 string "Flamethrower"
Zon 5 string "Klown"
Zon 5 string "HoodRat"
Fender 4 string P-Bass black w/ white pick guard
Fender 4 String P-Bass tobacco burst
Music Man 4 string Fretless Sting Ray root beer sparkle
Yamaha 5 string "Aztec"
Yamaha 5 string "Rat Rod"
Rickenbacker 4 String 4003
Rickenbacker 4 String 4003 "Mean Green"
On recent live BLu-Rays I have seen, he plays almost every bass on that list. He literally switches bass for practically every song... it's insane.
Personally, I almost NEVER actually play more than one bass during a gig, and I usually ever only have an extra for backup. Once I "warm up" to a bass and get acclimated to it, changing will freak me out.
But... then again, I'm not playing for Metallica and I don't have people lining up a mile long to PAY ME to play their gear either.