Having competitors can help a business in a sense because it can push the business to improve itself. If your firm has no competitors, you can be slack. You don't have to be efficient because no one is going to take your customers away from you. But if you have competitors, you have to improve your firm. You have to keep creating a better product and/or you have to constantly become more efficient at creating your product. Through competition, your firm is constantly being forced to get better at what it does.
I totally agree with what pohnpei397 said! If you have another model of what a similar firm is doing, you have a framework to compare/contrast to, as well as improve upon what they are doing in order to gain a competitive edge. There's no need to have nasty competition though, healthy competition is what makes businesses thrive afterall.