input: [Benefits?] Fairly instant traffic stream. Good for measuring conversions. [Risks?] A variety of competitive research tools make it easy for competing sites to clone your keyword list and strategy, minimizing your longterm profit potential. Even Google offers a Search-based keyword tool that tells competitors what keywords are associated with your site! You have to keep improving your conversion rates to not get priced out of the auction. A dumb (or deep pocketed) competitor can price you out of the market. Many businesses simply can't buy as much traffic as they would like to. In some markets Google partners dominate & those with a high quality score are given a favorable position. The second you stop paying, your search traffic is turned off. [Service] 
output: Google AdWords
options: S E O B o o k M e m b e r s h i p
options: G o o g l e A d W o r d s
options: A v e r a g e S E O P r o v i d e r
options: L o w E n d S E O P r o v i d e r
options: S E O C o n f e r e n c e s
options: H i r i n g a S E O M a n a g e r
options: O t h e r S E O T r a i n i n g S e r v i c e s