That depends on how exclusive you want your site to be and whether you are willing to share traffic if you grow in popularity. If your site is simple and straightforward, you could cut corners, but with URLs so inexpensive right now, it's really recommended that you go ahead and buy the redirect. Customers tend to remember the first part of your web address easier than they remember the tail extension, which means that they might accidentally browse to an incorrect site thinking it's the right one.