The hybrid laying hens are specially bred to convert feed to eggs extremely well. Some strains of Leghorns fall in that category. They are pretty bad as far as meat but are specialists for egg production. The Cornish X is also a specialist but for meat, not eggs. They are pretty bad as far as egg production. Nothing can touch the Cornish X as far as converting feed to meat. These assume you manage them to take advantage of that breeding. The dual purpose are not specialists but are generalists. They produce meat and eggs but not anywhere as efficiently as their specialists cousins.
Is raising dual purpose worth it for me? Absolutely. They fit my goals quite well. Is it worth it to you, I don't have a clue. I have no idea what your goals are or your value system. Your management techniques play a part. If your goal is how much meat will they pack on per pound or kilo of feed you buy, the Cornish X are probably for you as long as your management techniques match what is required to raise and process them.
The Cornish X do not suit me. I like to play with genetics in ways that they just don't work. I like to hatch my own eggs. I have to manage freezer space so I need flexibility in when I can butcher them. Mine forage for a fair portion of their food so my feed costs aren't as important as they are to some people. Eggs aren't that important to me, I give my excess eggs away. Size is not a hugely important criteria for me. There are only two of us so I can get two meals out of a small pullet, a large cockerel just means I get leftover chicken for lunch.
My dual purpose suit me just fine. But that doesn't mean they do you. That depends on your goals, conditions and management techniques. Rangers might suit you better than Cornish X, they do some people. We are all different. Your goals and preferences are what counts to you, not mine.
do they just end up eating more food than laying hens and then not providing as much meat as chickens bred for meat only?
Yes they do.
