Downsides to consider:
• You need a solid gaming PC (with a 2070 or better).
• Expensive ($1000 for the kit)
• Connected to the computer by a wire, awkward for "room-scale" VR
• Base stations provide great tracking but require setup (mounting high up in your room) and mean that the setup isn't very portable.
• Limited/janky access to exclusive titles. (You can hack around to get Oculus-only titles to work, but it seems rough and I haven't tried it myself.)
If you're not budget-constrained, I believe the Index will give you the best overall experience.