Pros: Good cooling, low noise, good looks, high quality, USB 3 in the front
Cons: Not enough fans included, heavy
The case is nice. It's high quality and easy to work with. It looks awesome and has a bunch of features. You can do virtually anything you want, 'cause it has room for so many things.
The Define XL also lowered noise quite a bit compared to my old case. I don't have equipment to test it, but subjectively, I think it's quieter.
I have to note though, that to even use the bottom HDD cages, you have to add your own 140 mm fan and to get proper GPU temps, you'll need a side fan. The stock case can cool a stock system, yes, but it's not that good. Adding a side fan and a bottom front fan dropped HDD temps 10 °C, GPU temps 10 °C and CPU temps 5 °C. The front 120 mm also helps quite a lot, but many users can't use it.
I think Fractal Design should get their act together and include at the very least another front 140 mm. It's not okay to let peoples' HDD's die a painful heat death.
While the price is high, I definitely think you get a quality product for that price. Maybe not the best cooling ever, but the materials are high quality (is it weird that I think the paint feels nice?) and it's a joy to use.