Your opinion on the new iMac M3 , 2023

That is correct. Your Lacie external SSD 1 TB is ideal to backup a 512 GB internal SSD of the iMac. If you get a 1 TB or 2 TB iMac, then you would need 2 TB or 4 TB Lacie external SSD for Time Machine backup. So if having a backup of your work is important, and 512 GB storage is enough for you in iMac, you should prefer getting that instead of a 256 GB iMac and then use the Lacie 1 TB for extra storage, and having to buy a new SSD for backup.

Personally I'm not liking the idea of not being able to replace the SSD (should the need arise) in my shiny new M3 iMac. If it failed then unless you shifted to a external drive your iMac is pretty much trashed.

Along those lines Apple should institute a motherboard upgrade path for newer processors and or memory and SSD upgrade proposes. Could be a good side-hussle for them to boot (pun intended).

Go with 256 internal, sell/return the overpriced, overkill Lacie 1TB,and buy one of these https://storage.toshiba.com/consumer-hdd/external for everyday use including backups.

Have a nice day!

The external SSD is ideal for a Time Machine backup, and its size should be at least double the size of your internal SSD. So 512 GB internal storage will be ideal for Time Machine backup to the 1 TB Lacie Pro.

One reason to prefer using internal storage over external storage could be performance of read/write speeds, if that is important to you. If not, another reason could be convenience. Another could be the ability to keep two copies for redundancy, in case something goes wrong (Murphy's Law).

iCloud Drive is essential for backup as well as file sharing, and also for syncing the most current files you are working on, and also syncing Photos across devices. If you happen to need more than 200 GB and want to save money, you can keep older projects archived in your new 512 GB iMac with 1 TB Lacie Pro to back it up, instead of paying for iCloud Drive.

telliott59 wrote:

Personally I'm not liking the idea of not being able to replace the SSD (should the need arise) in my shiny new M3 iMac. If it failed then unless you shifted to a external drive your iMac is pretty much trashed.

In Apple's current lineup, I believe that only the Mac Studios and the Mac Pros have SSDs on removable modules. Because the Apple Silicon processors act as SSD controllers, those modules are not standard M.2 SSDs; the only source for them is Apple, and so if you ever have to replace them, the replacement cost will be high.

All of the other Macs have soldered-in SSDs.

Something else you should be aware of: all Macs with T2 chips or Apple Silicon processors encrypt the contents of the internal SSD in real time. If you ever separate the SSD from the T2 or Apple Silicon chip which contains the decryption key, the contents of the SSD become so much unreadable hash. (Unless, perhaps, you are the NSA or KGB and have unlimited funds and time with which to try to crack the encryption.)

This makes it REALLY important to maintain proper backups. You CANNOT count on being able to "pull the drive" out of a failed Mac as a last-ditch substitute for never having properly backed up your computer in the first place. Relying on "pulling the drive" was always a very risky thing to do (what if that drive was the part that had failed?), but now, it's pretty much guaranteed not to work even if you have a Mac Studio or a Mac Pro.