To what length can the human lifespan be extended?
Many birds have a long lifespan and may outlive their owners.
Remember that cheaper alternatives will ultimately cost you more in the long term because they will have a shorter lifespan and you will incur periodic repair and maintenance costs.
It is Herschel's supply of superfluid helium which dictates how long its operational lifespan will be.
This confirms that with modern treatment regimens there is no significant shortening of the lifespan with PD.