I remain convinced that the S is a bad value long-term with very few exceptions.
Why? Because gPU-wise, 4TF for 299 is a way worse value than 12TF for 499.
Value per GPU teraflop:
XboxS: 13.3 Gigaflaps per $
XboxX: 24 Gigaflips per $
Based on GPU alone, the X is 1.8x the value. That's almost double. Now add in extra SSD, extra CPU and a BluRay drive and it's definitely double the value.
Now if you're 100% not going to upgrade your 1080p tv during the entire xboxS lifecycle, then maybe, MAYBE it makes sense. Or if you're giving it to that nephew that's playing it on a 22" screen, then sure, they won't notice the rez with a screen that tiny.
But outside of those cases, if you want an xbox and want long term value, get an X is my advice.