There's a small, but pretty interesting
You must be registered to see the links
over at the DAZ forums. It's interesting, because each piece of software performs differently for a graphicscard. Actually, each Daz Studio scene will perform differently on a given graphicscard as well. But, benchmarks, especially for the specific piece of software you intend to use, do give some crude idea how a GPU performs, and how that performance translates to the price of the GPU.
For example, those RTX Titans render a scene about 15% faster than an RTX2080Ti. But, their pricetag is more than 100% higher. Which brings me to the conclusion that unless I desperately needed the 24GB of memory from the Titan, or won a few million in the lottery, the Titan would be an extremely inefficient waste of money to me.
I settled on the RTX 2070 (pre-super) a while back myself. If I had had a bigger budget, I would've totally gone for the 2080Ti, since, with large scenes, I do have to be cautious about the 8GB of memory on my GPU, and 11GB would definitely make that a bit easier. But when I only take renderspeed and the cost of the videocard into consideration, my 2070 does beat the 2080Ti.
So, in my opinion, it is worth considering what features you need (memory & renderspeed), and figure out how much a benefit is going to cost. I could make 24GB scenes, warranting a Titan, but those are not the scenes I am generally interested in making, so the 24 GB benefit is not be a consideration to me. Which leaves render speed and price. A 15% increase in renderspeed at double the cost? That's soo not an option to me.
The 80% renderspeed increase at double the cost for taking a 2080Ti instead of a 2070 alone is a much closer consideration, and I do occasionally go over that 8GB limit of my 2070 (which means I have to spend time tweaking textures and lights, hiding more assets that are out of scene, etc.), making the 2080Ti with 11GB indeed twice as useful for my purposes.
So, it's personal, but it is definitely worth it to consider the options, and think through what features you need and which features you probably won't ever use.