Public measurement platforms composed of low-end hardware devices such as RIPE Atlas have gained significant traction in the research community. Such platforms are indeed particularly interesting as they provide Internet-wide measurement capabilities together with an ever growing set of measurement tools. To be scalable though, they allow for concurrent measurements between users. This paper answers a fundamental question for any platform user: Do measurements launched by others impact my results? If so, what can I do about it? We measured the impact of multiple users running experiments in parallel on the RIPE Atlas platform. We found that overlapping measurements do interfere with each other in at least two ways. First, we show that measurements performed from and towards the platform can significantly increase timings reported by the probe. We found that increasing hardware CPU greatly helped in limiting interference on the measured timings. Second, we show that measurement campaigns can end up completely out-of-synch (by up to one hour), due to concurrent loads. In contrast to precision, we found that better hardware does not help.