yeah i have not tried coco but i here it is great. but for me u cant beat the automation of full hydro and thats what the control box is all about.
u could do without it but u would have to have your res at the same level as your waterfarms. for me i want easy access to my res. i want to be able to easily disconnect it and take it upstairs if i want and i want everything to be automated im sick of changing the tiny waterfarm res every 2 days with this new system i hope to be able to fill it once a week and forget about it. in theory i could go away for a week and my plants would be fine bigger res means i could leave it even longer if i wanted so for example if i wanted to go on holidays i could just attach a larger res and everything would be apples for 2 weeks or whatever u know. no more stress