Which one should I get? Should I spend the extra $170 for the ASUS?
The Strix will OC better and run quieter. In general, the higher priced models are binned for better GPUs and memory. Also, the coolers are usually better. Based on reviews from guru3d and techpowerup (among several others from respected publications), the Strix model is quite good. Considering that you are getting something like a 2080 Ti, I would definitely step up and get the Strix model. The only Gigabyte model that is worth considering is their flagship Aorus Xtreme card but it is even more expensive than the Strix.
If sticking with the hardware the cards come with, get the Asus one. If going into a waterblock, go with the Gigabyte.
as long as you mean Windforce and not Windforce OC, then the strix is the better option (kind of, sort of). that said, if you can find a Windforce OC or any of the Aorus or Aorus X cards for the same price or less, those are technically better for overclocking on due to the higher power limit on them. here is a list of what you get power limit wise vs a reference Nvidia card:
Nvidia FE: 260 watt base, 320 watt with offset
GB Windforce: 250 watt base, 280 watt with offset (NON-A DIE!)
GB Windforce OC: 260 watt base, 366 watt with offset
GB Gaming OC and any Aorus X type card: 300 watt base, 366 watt with offset
GB Aorus (non-x): 275 watt base, 366 watt with offset
Asus Strix Gaming OC and Asus Strix OC: 260 watt base, 325 watt with offset
any EVGA FTW3 Ultra Gaming series: 300 watt base, 373 watt with offset
MSI Gaming Trio and Gaming X Trio: 300 watt base, 406 watt with offset (DOES NOT HAVE POWER BALANCING!)
any MSI Lighting card: 350 watt base, 380 watt with offset
If you can afford them (and find them) and really want to overclock far:
Galax/KFA2 HOF (Hall of Fame) cards: 300 watt base, 450 watt with offset
EVGA Kingpin: 361 watt base, 520 watt with offset and LN2 Bios selected.
If you're wondering what wattage potential has to do with overclocking, it basically will (partly) determine your max feasible overclock. let me illustrate with personal experience:
I owned an EVGA RTX 2080 Ti Black. this card has a 250 watt base and a 280 watt power limit with the 12% offset. 280 watts is generally not even enough to keep clocks up on this card at stock under a gaming load. clocks were frequently dropping and/or fluctuating because the card simply didnt get enough power to be stable at those clock speeds. this is why I now consider the FE's 320 watt to be the minimum you really want JUST TO MAINTAIN stock clocks under load. as for overclocking, cards like mine with low power limits do not overclock well at all. This lead me to hardware mod my card (no, I dont recommend most people to do this). This modification let me have effectively a 406 watt base, and a 455 watt limit with the offset. my overclocking went significantly better after that (2260mhz on chilled water was stable as compared to stock when it was hard to maintain 1950mhz).
all in all, instead of focusing on aesthetics alone, look for cards with decent PCBs and Power limits, unless you have no plans to overclock anything. my answer to your question is essentially that the Strix you have listed is not worth the extra money over that Windforce, because that bump in money could buy you a much nicer card in terms of overclock potential. if you dont want to overclock, the Windforce will do fine. If you want more room to overclock, dont get either of those; get something better.
Thanks everyone. I don't plan on overclocking at least right now.
Just want a decent card. Sounds like the Strix is the way to go for me.
asus beforece rtx 2080, because it has a better design and it is faster and if you are running 4k gaming and or 4k uhd videos or 3d rendering with a decent cpu then yeah I prefer it is pricey but id get it