A PS is one of the most important components of your application because this document, when written correctly, will offer your readers, namely the admissions committee members, a quick glance into your life story so far and which direction you plan to take. You are inviting the reader to share your experiences as you disclose who you are as an applicant. Through your PS, you are providing them a general picture of your background and qualifications, knowledge of which will allow them to evaluate your suitability for admission to their school accurately.
Remember, your personal statement is 'personal' in nature so it is in your best interest to be sure that all the information you provide is in fact your information. By starting with one sample and taking some ideas, then moving on to another and taking additional ideas, and so on, you allow your true self to come out in the finished product and this will give you the best shot at gaining access to the school of your choice.