Tried the changing of editions and works great. I like that you can see editions and page numbers.
Hope maybe it can be put into simple linking too (to see which edition is chosen), but I usually download goodreads ID with metadata so I rarely need to link manually. And now it's easy to change editions.
The only problem could be in changing edition while in goodreads it remains the old edition. So you need to change both. Maybe there is a way to check which edition is on the shelves? I often add books on goodreads manually (like my to buy list or the books added before I started using calibre or the books I see my friends reading etc) so edition in calibre and goodreads are often different. Downloading/syncing often shows which since you get no results for those books. Unless you end up with duplicates on goodreads. Which can be removed in batch edit in case somebody doesn't know. And again you need to see which edition is in calibre/ which to keep.