OM-D flash on XZ-1?
I think you'd be better of with an FL-300R.
That should work well with the xz-1, and if you got the white one it would match color wise. It has the bounce feature, internal batteries, and is small.
There have been some posts in this forum about the FL-300R and XZ-1 not working too well (at least as a remote flash). You might want to check them out before buying anything.