The most important factor in deciding whether to use paid URL inclusion is to decide if it’s a good investment. To figure this out, you have to look at the overall picture: what kind of product or service are you selling and how much traffic are you dependent on to see a profit?  If your company sells an inexpensive product that requires a large volume of traffic to your site, paid inclusion may not be the best investment for you; the biggest search engines do not offer it, and they are the engines that will bring you the majority of hits. On the other hand, if you have a business that offers an expensive service or product  and requires a certain quality of traffic to your site, a paid URL inclusion is most likely an excellent investment.

Another factor is whether or not your pages are updated frequently. If the content changes on a daily or weekly basis, paid inclusion will insure that your new pages are  indexed often and quickly. The new content is indexed by the paid spider and then appears when new relevant keywords are entered in the search engines. Using paid inclusion in this case will guarantee that your pages are being indexed in a timely manner.
You should also base your decision on whether or not your pages are dynamically generated. These types of pages are often difficult for regular spiders to locate and index. Paying to include the most important pages of a dynamically generated website will insure that the paid spider will index them. Sometimes a regular spider will drop pages from its search engine, although these pages usually reappear in a few months. There are a number of reasons why this can happen,
but by using paid URL inclusion, you will avoid the possibility. Paid URL inclusion guarantees that your pages are indexed, and if they are inadvertently dropped, the  search engine will be on the lookout to locate them immediately.

As you can see, there are numerous factors to consider when it comes to paid URL inclusion. It can be a valuable investment depending on your situation. Evaluate your business needs and your website to determine if paid URL  inclusion is a wise investment for your business goals.