Other than the cosmetic theme, and both being alphanumeric, they're completely different machines. Like everybody else has said, pinbot is a superior game to most people. A lot of long technical shots to hit, and can be obscenely difficult.
Bride has the great sound package, has a more flashy and shiny presentation, and is more accessible to non-pinball people due to rules and the ramp shot.
No need at all to worry about them being too similar, they're actually very far apart.