Startupheatmap.eu is a platform dedicated to identifying the best thriving startup ecosystems across Europe. It quarterly maps and ranks these locales, providing insightful data and analysis to entrepreneurs, investors, and policy-makers. This review encapsulates its myriad features, key functionalities, and feedback on its overall user experience and business value.

1. User Interface (UI): The website has a user-friendly interface that is easy to navigate. The heat map dashboard, where the data intelligence is visually presented, is interactive and intuitive even for first-time users. However, a faster and more responsive UI could further improve user engagement and satisfaction.
2. Coverage: Startupheatmap.eu covers a wide range of locations across Europe, which provides a refreshed perspective on the startup landscape and challenges the traditional focus on major tech hubs. For startups seeking exposure, entrepreneurs in search of opportunities, or investors looking for promising projects, the platform offers an expansive array of choices.
3. Features: The feature-set includes a heat map, ranking of startup locations, trend analysis, and detailed city reports. These comprehensive features impressively cater to a broad range of user needs - from startup entrepreneurs who want to compare locales, investors seeking potential opportunities, to policy-makers looking for data to inform their decisions.
4. Analytics and Insights: The insights provided by Startupheatmap.eu are well-researched and data-driven, conveying an in-depth understanding of the dynamics of the startup ecosystems. By visualizing these insights as a heat map, the platform enables users to grasp the information quickly and easily.

Its wide coverage, extensive features, and data-driven insights make it a unique and potent tool for unearthing the best startup opportunities across Europe.