SSDs still can't compete on byte/dollar. You can get 10TB of magnetic drives for less than $200 while that much in SSD will cost you several times as much. (Certainly the gap narrows for smaller drives, and most users don't need that much space, so SSD by default makes sense.)

That’s true. But I don’t really care about the performance of my external hard drives. They store movies, photos, etc where as long as the hard drive can keep up with the streaming requirements - any hard drive can - it doesn’t matter.

The other purpose is backups. Again if my backups are slow, who cares?

> I don’t really care about the performance of my external hard drives. They store movies, photos, etc

I care very very very much about the speed of the drive that stores my video files. I need to be able to open and seek through them quickly so I can find the clip I'm looking for. When you're working with ProRes stuff, this becomes a big deal.

Luckily, good quality spinning hard drives can be fast enough, at least for my needs. Unfortunately, they're only fast enough when they're not running APFS. :(

> Luckily, good quality spinning hard drives can be fast enough, at least for my needs. Unfortunately, they're only fast enough when they're not running APFS. :(

Nothing prevents you from putting for videos on an HFS+ volume and use it from Catalina. It just can't boot from one.

Good point—this conversation got a little muddled. I actually use either ZFS or NTFS + Tuxera for external drives on Mac, which works great (especially ZFS).

Just listing a bunch of photos is going to have terrible performance on APFS. They don't need to make it work amazingly on hard drives, but they need to do some basic things like lumping together related metadata.

What benefits do you really get from using APFS on external magnetic disks that are really so significant that you wouldn’t just use HPFS?

Snapshots are always good.

No but these are low end machines, the bottom of the range. There is no option to upgrade them to 10TB.

What about the macs which shipped with magnetic drives? What should the owners do, when Mojave support runs out?

Why not both?

Keep using HPFS...

Supposedly, Catalina does not boot any more from HPFS, so how is this good advice?

In the context of where you store photos, videos, etc where you want to be able to use massive cheap magnetic media you would use an external hard drive. You would still boot from your internal hard drive. If you have a Fusion drive, more than likely the OS would be on SSD. If you were unfortunate enough to have the cheapest iMac with only magnetic hard drives - it would still be less of a pain and more performant to buy a small SSD external drive as a bout/app drive and an external magnetic drive running HPFS.

A 1TB sata SSD costs about $120. Worthy upgrade on a +$1000 machine imho.

I completely agree with you, but it's very difficult to replace the 2.5" drive in recent iMacs, and Apples price for the SSD is unfortunately not $120.

In my opinion the base included option should be a reasonably sized M.2 SSD, with an option to increase the size of said M.2, or to add a 1TB (or larger) 2.5" drive as an extra if more storage is needed.

Replacing the HDD on an iMac is non-trivial. This is not only due to the fact that you have to unglue and then re-glue the screen, but there is also a non-standard thermal sensor on the Apple HDDs which you need to circumvent when putting a standard SSD in which doesn't have that sensor (if you don't, the iMacs fans will always spin at 100%).

It’s a desktop. Why replace the drive instead of just using an external drive? I could understand not wanting to lug around an external drive with a laptop.

And how exactly do you use an external drive? Due to the limitations of the internal drive, I have used quite a variety of external drives with my iMac, but no solution is really good and all are much inferior to an internal drive. USB 3 drives work the best, but are limited and speed as is the number of USB ports on the mac. Going via hubs is possible, but reduces the reliability of the connection, I keep getting drive disconnects. Also, I haven't really been able to find a reliable Thunderbolt 2 drive.

What’s wrong with the higher end TB2 SSD drives/enclosures?

Which ones? Can you list one, which doesn't disconnect from time to time without unmounting the file system? I used a thunderbolt enclosure from OCW and eventually the file systems were corrupted beyond repair.

I’ve never had that problem, using a Buffalo drive station mini (which I upgraded the 2 SSDs without issue either), neither with Akitito thunderbolt 3 4-bay thing. Both products are discontinued though. People complained about the Akitito one disconnecting on Amazon, from memory someone said the cable was a bit loose. I used an Apple thunderbolt cable from the beginning (because someone left out the included cable and it was coming from the US to NZ over Christmas...) and I dunno if that plays a part, but it’s snug and I’ve never had an issue.

I would not want to be booting off an external drive.