Humanitarian OpenStreetMap Team proposed the fAIr project (https://fair.hotosm.org/) - an open-source AI-assisted mapping tool. This study describes our user testing organized to compare AI-assisted mapping of buildings in the fAIr tool and classic manual mapping of buildings in the JOSM editor without AI assistance. 26 participants took part in the experiment. Efficiency (number of buildings mapped per minute), effectiveness (proportion of buildings mapped correctly), and satisfaction (feedback from participants) were analyzed.