just checked the store page it's 15.1GB. this standalone version looks about the same as S&S1 Q2 standalone graphics wise, i bet it's still got the core gameplay so is fun but nothing fancy to look at. the pcvr version looks the 1 to have and that's what i'm waiting for although i will buy the quest 2 version today if it's cross buy.
That 311mb looks like it might be on the money.
God awful, it genuinely looks like a 20 years old average PS2 game. There's no way they can release this to the PC market, no wonder they kept it under a shroud until release.