A:Answer the 512gb is the quest 3 and the 128gb is the quest 3s. the 3s is more akin to the quest 2, but only marginally better. the quest 3 is where all the upgrade/innovation went to (better resolution, better processing power, etc.). it honestly just depends on your needs and your budget. if you think you'll be using it a lot and can comfortably afford it, I highly recommend the 3 over the 3s. it also depends on if you'll be using it more for the standalone games or if you plan on doing pcvr. if you're doing pcvr, you won't need as much storage space on the headset itself. in the end, it really just comes down to how you plan to use it and how often you plan to use it