This study addresses the Out-Of-Box Experience (OOBE) usability issues of Free and Open Source Software (F/OSS) considering outcomes of distributed development process and high number of available product choices. A methodology is presented, usability experiments are conducted and results are discussed. The objective was to determine key factors that affect usability of F/OSS during OOBE and first hours of use. We concluded that OOBE of F/OSS was significant in software usability perception and possible adoption. User experience, visible structure, consistency and functionality of the interface had significant impact on OOBE and first hours of use. Neither online support, nor product box appearance appeared as important.