I have 2 main work machines, 2 secondary pcs I occasionaly use at work, 2 laptops, a netbook, and a home machine. Keeping all those uptodate with Opera is a pain. That is until I drank the DropBox koolaid.
Use Opera Classic and install it into a directory within your DropBox folder. Now Opera is always 100% in sync across all my machines. If I install an updated version on one machine, it automatically updates ONLY the files it needs to update on the others. It also keeps all your bookmarks, toolbars, and other widgets in sync.
tip: if you do this, edit your Opera ini or "opera:config" and switch the location of the opera cache directory OUTSIDE of your drop box. If you leave your cache directory in your dropbox, it will grind away and slow you down as it syncs your cache all the time.
I guess you'd have to disable Opera Link then, eh? ;) I used to sync my Opera installs using Microsoft's Live Mesh. However, I found that I liked having different setups at home and at the office. I stopped syncing and just use Opera Link now.