The development and maintenance of UML models is an inherently distributed activity, where distribution may be geographical, temporal or both. It is therefore increasingly important to be able to interchange model information between tools – whether in a tool chain, for legacy reasons or because of the natural heterogeneity resulting from distributed development contexts. In this study we consider the current utility of XMI interchange for supporting OSS tool adoption to complement other tools in an embedded systems development context. We find that the current state of play is disappointing, and speculate that the problem lies both with the open standards and the way in which they are being supported and interpreted. There is a challenge here for the OSS community to take a lead as tool vendors gear up for XMI 2.0.