No one in their right mind would expect this hardware to stay relevant for more than 1-2 years.
If you can't afford to spend $600 once a year, get a better job, or stop buying expensive toys.
I'd be totally OK with it costing $1000 if it could really provide a great VR experience.
The interesting question is how long before this version of the Rift becomes obsolete, or will Oculus provide a contract-based upgrade plan (like for phones).