soil is more forgiving, i havn't gone total hydro but i am using hydro feed with coco fibre and clay pebbles and its going fine , i feed every time i water and water when the pots are dry . the thing is about hydroby the time u realize sumthing is wrong its to late , with soil normally a good flush sorts most problems . After a flush u can then judge what is up with ur plants ( i.e. lacking in stuff). my advice would be to grow with soil and see how u go . if no problems and the weed is good then don't complicate things by going total hydro.
PS . if u do use coco fibre go a 50/50 mix with clay pebbles. u won't be disappointed.