I did for the first time last year. One of my girls went broody so I brought some fertile eggs for her to sit on. I got a quick growing meat bird variety. The birds had a pretty much free range life and were ready for the table at 14 weeks. I had 8 delicious birds weighing between 5lb and 6lb. The big problem was their appetite, they required a huge amount of supplementary feeding. So much so that it wasn't financially viable to grow that variety again.
This year when I had a broody I got some Light Sussex fertile eggs as I needed some females to replace some of my layers who are entering retirement. I have 2 Cockerels who will eventually go in the freezer. As these birds are a pure breed they grow much slower and I expect them to wiegh less. Again they have been pretty much free range, but the big difference has been the feed bill. I doubt I've used a third of the amount I used last year.
So Once I've done a taste test, I think I'll stick with a purebreed.
Next thing on the agenda are Quail. A friend keeps them and not only does she make a good income from the eggs, they breed like Rabbits and she has plenty for the table, for not a lot of money!