Depends on how you define "viable solution", I guess. Yes, 2886 is the current (and final) firmware build.
As long as it's working, then a free OBi is better than no OBi, or buying a new one. If/when it dies, recycle it.
If you want to give it away, be sure to first delete the device off of your OBiTALK web portal account, and then factory-reset it, or the next user won't be able to assign it to their account.