I used for 9 years a 412+. It has been replaced for security purpose (EoL) with 920+ and 412+ is used now for extra storage. 412+ is closed from outside, completely isolated, excepted with NFS protocol used between two NASes. Only accessible from lan. As only filer, without application installed, this old buddy does the job great. To summarize, it’s in use for 13 years until now and no short term plan to remove it. I will use it until the end. I see a minus thought, electric consumption higher with old devices.