French = more time consuming
French = more effort to score well.
Spec is really fun if you are good at maths, and if you do methods there is a lot of overlap so you can study for 2 subjects at once!
I like learning French but at as subject it is easily my least favourite because it's not something you can improve at quickly. With maths and science subjects you can speedrun the course, but not with a language. There are too many words. Still, I think it's good to do a language just for some variety in your subjects.