Oh yes, long-term reliable storage is expensive. I keep advocating a combination of local ("onsite") and remote (cloud or just disks at a physically different place) as a good combination.East Wind Photography said:Oh yes there is cost to long term SSD storage. Requires fairly constant rewriting of the data to refresh th storage charge and ultimate failure of the memory location. SSDs are getting better though but i would never use them for long term storage. I use redundant USB drives for long term storage. USB has the best backwards compatibility support. My version 1 USB drive still works in a usb 3.0 port. Relying on things like SATA interfaces may go by the wayside with MFM, RLL, Scsi and soon to be IDE.kaihp said:I would only use an SSD as the 'working drive', and then have some spinning rust for bulk storage of the things you aren't working on. I use WDC Reds in my NAS. Today, I'd probably choose WDC Red Pros, as they are a bit faster (7200rpm vs 5700rpm) and not that much more expensive (+10% IIRC).
Whatever you use it will eventually be obsolete unless you refresh about every 10 years or so. Possibly less.
Cloud storage is an alternative but it just moves that refresh onto a 3rd party that you hope you can trust with your data.
USB drives are a good choice. Like you say, the interface is pretty ubiquitous and has been around since 1996.
A good alternative is a NAS (Network Attached Storage) enclosure with disks inside, which connects via Ethernet. Ethernet has been around 'forever' (introduced in '80 and standardized in '83) and there are no signs of it going away either (we're at 1Gigabit/s for end-users and 100Gigabit/s is standardized).