Music performance anxiety (MPA) is considered non-beneficial but its debilitating aspects are not directly addressed in current questionnaires ("general MPA"). Together with general MPA, we assessed "debilitating MPA" with questions about aspects that debilitate musical performance. In addition, since musicians often experience a beneficial aspect of MPA in the form of a performance boost, we assessed this boost with additional questionnaire items. The first goal of our questionnaire survey was to investigate whether general MPA is perceived as part of the same continuum as performance boost. Our second goal was to determine which aspects of MPA may lead to a downward spiral of a musical career. The results of our questionnaire survey of 320 professional and student musicians show that general MPA does not lie at the other end of the spectrum of boost. Instead, debilitating MPA with a weak career impact was influenced by boost and performance confidence. Debilitating MPA with a strong career impact was influenced by health and mental distress. Debilitating and general MPA were related to perceived pressure, whereas boost was related to perceived support. Perceived pressure and support might be more accessible anchor points in the treatment of MPA, and in the maintenance of a stimulating level of boost.