$0.02 from a long time DWC grower...
I prefer DWC, it's been the absolute easiest method I've used to grow the cleanest cannabis. Having to keep the res at 68F means my canopy is at 71-72F, perfect for high quality cannabis. Using reverse osmosis water means there are no excess elements from my water for cannabis to absorb. Using pharmaceutical grade nutrients, balanced for cannabis and a full pH swing, I grow what people call "The smoothest, softest hitting, most flavorful and aromatic,
organic bud I've ever tasted."
How do I do it?
Mono-crop per reservoir, all plants require the same feed level, use clones for exact timing and nute requirements
Feed the bare minimum nutrients necessary for full and robust growth
Watch your transpiration rates, keep them high as oil production starts (this auto 'fades' the plants)
Change your res out (one and only one time) at the end for plain reverse osmosis water. Osmosis will pull excess nutes from the plant.
Cannabis is a dynamic accumulator, any excess of an element and any element absorbed which is not needed for growth... gets packed into new growth where it stays forever. You can flush or fade forever and that junk isn't coming back out. Only elements still moving in the plant and a few select elements 'properly' used for new growth can be flushed/faded out.
When done right your cannabis will burn smooth, feel soft and cool (difficult to tell you're even getting a hit) and will be so full of flavor and aroma it'll knock your socks off. You'll be biting the smoke as you exhale, it's that damn tasty, even after being burned.
The last hit in the bowl will barely have a burnt taste or smell to it, almost as tasty and delicious as the first hit. The ash will be light and fluffy, slightly off-white, and drop out easily with a tap or puff of air.
Cannabis flowers like this...
So... I recommend both fading and flushing cannabis, regardless of the methods you use to feed it. It makes a significant difference in the end product.
Douglas