I just don't have the time to do all of the link building and using a service to get 50-100 links for a reasonable fee sounds like a good way to augment what I'm doing..
The flaw in this statement is "reasonable fee". There is no such thing as a good link builder at a reasonable fee. You can get people to get you tons of worthless links for cheap all day long. Good link building is expensive. Your lucky to get one or two good links a day on average when you do it right. It takes a lot of time and hard work to build quality backlinks. Also you have to have good content to link to. When I build links for clients most the time content needs to be created to attract links. Creating backlinks is an uphill battle if your website is not worth linking to.