>>273609309
Do you have 1000 dollaridoos lying around? 
>Yes
Buy the Index
>No 
Buy the Rift S
The Index is objectively better in every aspect than the Rift S, but both are good. It's only about if you're willing to pay more for the increase in quality. Look at some videos online to see how big the difference is, and compare that to how comfortable you are with $600 more not in your bank.