My suggestion is to try both and see how it goes for you. There are differences and we all have our preferences. What should be guiding you is your preferences, not mine. So have fun with it and eat your mistakes as well as what you get right. And base your decisions on what you see yourself and how they fit your goals and expectations.
I personally like dual purpose. I like playing with genetics so dual purpose fits better with that. I have to ration my freezer space, especially in summer and fall when I have a lot of fruits and veggies to process. Smaller batches of meat throughout the year suits that much better than a large group of birds that have to be processed at the same time.
It took a few years to work out a system that works well for me. I think you need to do the same thing, determine what works for you. Don't expect to get it exactly right the first time. But with a little experience, you will home in on it.