If you're looking for contacts and leads in the media and advertising space, this is a very useful tool. I only have the light version, so I only have access to contact information, which is good for our budget. It makes it very easy to find the right people to get in touch with on media and advertising opportunities. If you pay more, you also get good info on their spend, spending categories, and spending periods.
MediaRadar was the best tool in the native advertising space. We use a combination of multiple resources like Alf, Winmo, Seller Crowd to get a holistic view. Every platform has its unique advantages and disadvantages over the others. MediaRadar's support is outstanding and makes it easy to work with them. Winmo has a more comprehensive view of media budgets compared to MR.
Since I use Media Radar to locate brand information as well as contacts for outreach, it has positively impacted the amount of opportunities my organization receives.