I prefer to work and use APA, but that is because I am most familiar with it. After about 22-24 classes having paper for each I used MLA format in only one. I feel pretty experienced in working with it now. It was entirely brand new for me at the beginning. What really helped was that my first class at National University was ILR 240, introduction to literary research and writing. In this class our text was a guide named Bookmarks. I have used this book in every class since. Now that I have started this course, I have referenced The Little, Brown Essential Handbook. I will continue to want to use APA style in the future.
Documentation is vital. As a reader we need to know where our information is coming from. We need to validate the authority and agenda of sources. As a writer we need to give credit to our sources for their work. Citation also gives us an out, saving our integrity if our source in the end is mistaken or incorrect. We can later write a retract or an update. I find the easy part is applying citation with in the body of text. I find the most difficult portion, being the actual researching portion, especially when searching for precise studies to support a claim. I find that the University's online library is the most helpful and instrumental in my research. I also like Google and Yahoo search engines.