Thanks been watching reviews on Youtube, some say the passthrough is better on the 3S cos of IR and its darker on the 3?
And is the screen / view / resolution THAT much better?
The pass through is the same, but it should look better on the 3 as the lenses are a lot better. The quest 2 lenses are not as good.
It is substantially better.
EDIT:
Think of the Quest 3S as the Xbox Series S basically, it has a fast enough chip and same pass through that it runs everything so you have technically the same experience, and it's designed to be at the price point that most (in the US) can buy one with what's left at the end of the month as an impulse purchase.
The Quest 3 is the Xbox Series X, it has all the extras that make it a good product, the lenses mean everything just looks good rather than just works.
If you don't have the income to get to a Quest 3 / other things have priority, then consider the 3S, if you can save up for a little longer, the Q3 is just a better product/experience. The Q2 my biggest issue were the lenses, not having stuff clear/sharp all around, forced to look straight at anything to be able to read the text properly. Going pancake lenses sorts out that issue and for me is a huge QoL difference.
If you're only playing shooters, it's kind of okay, annoying if e.g. maps that are further distance, and it's generally fine for stuff like beat saber and pistol whip, but if playing any SIM stuff like racing/VTOL, or other story line games, or stuff like Demeo, it gets tiring fast having to look dead center at stuff rather than just look at it.
I think you also have to use both in person to understand how much of a downgrade the lens difference is, so if you end up getting the Q3S, you'll be happy with it I think.