Absolutely. I would have more time to think about a question rather than rush it and write practically illegibly so that I have time to finish the paper and maybe check it. I write fairly slowly so that it is readable but in my GCSE English lit exam I didn't finish one of the questions because I ran out of time from needing to plan as well as ensure my writing was readable.
I know somebody with extra time who doesn't really need it, never uses it (he just sits there and waits for it to be over) and complains he has to sit there when the exam is over. And he gets a laptop in essay exams. I think that if you are allowed a laptop then you don't need extra time because the use of a laptop already speeds you up - therefore eliminating the need for extra time.
I also know someone who is deaf and got extra time in their exams. They didn't do any exams that required listening like a language or music, but they still got extra time in all their exams. I don't think that is fair to everyone else because although it's a disability in everyday life it won't impact her WRITTEN exams. Completely unfair.