I have both going right now ebb n flow and fox farm ocean forest outside. Soil in containers is a lot less hassle...sort of. The only thing that gets on my nervs is having to drag my ass outside every morning before work to water them. I like the hydro because it is hands free...more of the time. I mean there is the res change once a week, but I only have to add water twice a week and check the ph 3 times. Outdoors I have to worry about the bugs, the mildew, the mold, and animals, and wind. I would say the biggest reason to go with soil is like dangly said...is that you use so much less nutes. And when you have expensive ass advanced nutes...saving them is great. I've never done a side by side grow like this so I am really excited to find out how the 2 will compare.