Much like an artist choosing the correct medium to influence his masterpiece, your method of writing could affect your process. In fact, a 2003 study published in the "Journal of Pragmatics" found that writers who used computers wrote more choppily and tended to revise in blocks, while pen-and-paper writers tended to approach writing more methodically, revising at the end. Neither is the "correct" way to write, but taking your chosen process into consideration can help you choose a method that fits your style and personality.
If you're the type of writer who draws inspiration from certain locations or situations, you may love the pen-and-paper writing method. With a pen and paper tucked into your bag, you're always ready to jot down a few lines of prose or dialogue as it comes to you. Of course, laptop computers make it easier to write on the go, if not everywhere that a pen and paper can. Still, you may need to plan ahead to bring your computer, which could interfere with the creative process of writing when inspiration strikes.
Comfort is a truly subjective topic when it comes to writers. To some, it means being able to write for hours on end, which can be easier with the help of a keyboard and less cramped muscles from writing by hand. For other writers, comfort means the ability to write in the most natural way possible, which means reverting to a pen and paper and shunning modern technology. Although it's true that your hand can become cramped when writing with a pen, you should use the method that helps you feel comfortable and inspired.
It may seem as though using a computer has a clear advantage over writing when it comes to the editing process. With a mouse click, word-processing programs can read through your work and point out poor grammar and spelling mistakes. Still, some of those mistakes may have been introduced via typos, a non-issue for those writing by hand. Although a computer does offer the benefit of modern technology, choosing a medium is a writer's choice. What is right for one writer may not be right for another.