I don't know about other brand thumbs, but a Kubota thumb is substantially more expensive to install as an addon. I believe its a $1300-$1500 option from the factory. I had one quote from a dealer of about $2500 to install a factory thumb, including labor to install auxiliary hydraulic valve kit, hydraulic lines, and install quick attach coupler to bucket (pin-on backhoe bucket can't be used with factory thumb).