The
wiki: E-book Reader Matrix includes the PocketBook 360° with similar hardware to the Opus but different firmware. The 360°'s plastic screen cover is a neat idea. I don't think it will support mobile ADE (i.e. not DRMed ePub) though.
Now that folders have been added, the Opus has a better library view (including thumbnails) than the Hanlin and the device looks cleaner. We don't know about the quality of the ePub/PDF support yet, i.e. how different their mobile ADE implementations will be.
I like my EZ Reader and I will probably be getting a EZ Reader Pocket Pro (Hanlin V5) as soon as they are available. Having at least a few different firmware variants to choose from has been a plus on the V3 (most are very similar, but Lbook's is distinctive). OpenInkPot is also a nice option. This could in principle be ported to the Opus, but it should be easier to port to the V5.