"you can apply with a MECIR, whether it gives you an advantage or not, it is up to recruitment to decide on that. I don't think it matters as long as you have the minimum requirements and fit the other criteria."
It's unlikely a MECIR will give you any advantage, or disadvantage, for that matter. What they are considering when they are assessing you is what sort of pilot you will make in the future. Sure, having a MECIR may show you're pretty keen to keep moving on with your flying and progress as quickly as possible, but the important thing is for them to see that you will make a good pilot when you are flying for them. Being able to demonstrate these qualities in an interview is much more important than failing to show them these qualities but having a MECIR.