Versioning helps users to keep track of different sets of edits on a document. Version merging methods enable users to determine which parts of which version they wish to include in the next or final version. We explored several existing and two new methods (highlighting and overlay) in single and multiple window settings. We present the results of our quantitative user studies, which show that the new highlighting and overlay techniques are preferred for version merging tasks. The results suggest that the most useful methods are those which clearly and easily present information that is likely important to the user, while simultaneously hiding less important information. Also, multi window version merging is preferred over single window merging.