I don't know how much they factor in to the admissions process, but it is probably a good idea to put some time into your personal statement.
I tried to do it myself at first, and just kept coming up short of the feeling I wanted, and the right information to provide within the word limit. Ultimately I ended up using the EssayEdge service. I wanted it done really fast, so I went all out and paid for the super-duper alleooper premium service ($200!)...It turned out awesome and the person that helped me did a wonderful job of meeting all my criteria and making me sound like I was "cream of the crop".
However, I think if you have time, some writing skills, an English professor that can do some proofreading and if you read some sample essays, you could probably compose an essay just as good.
Also, ask someone to read it.
Make sure that your essay is interesting and keep your reader awake.
Try not to repeat facts that already said elsewhere in the application, but how do those activities affect you as a person.