I just ran a benchmark on merging files using Eclipse which then calls subversion and running subversion manually on a 28MB repository.
The results are interesting.
svn merge destination_url@HEAD source_url@HEAD destination_folder
took exactly 7 minutes
Using a subversion merge in eclipse on the same repo and revision took 10 minutes.
Take away: use svn merge on the command-line.
Ya, I’d love to go back to using git.