Mojave on Fusion drive

[iMac-Gyver]

Have same machine as you and have been contemplating upgrading from High Sierra to Mojave. Am thinking, having read this thread, that I may be best just to leave as is. Unless anyone has any better advice?

If it works and you don't care about the Dark Mode (it's a revolution ;-) I would say stay as you are!
The only problem is with a new OS each year (Grey mode?), there is a time where it's gonna be too old to surf the web, but in the meantime don't hurry!
By the way, my previous post (see a copy below) was a question for #Person Man 2:
if you still follow this tread, a reply would be much appreciated : )

"Hi!
I'm currently fighting to find a solution for my Late 2012 with a 3To fusion drive and this f…ing APFS.
I find incredible Apple doesn't even give the choice of the file system, especially for people using a spinning hard drive or a Fusion drive as APFS is making it nearly impossible to work with…
Anyway, your solution seems the best I read so far (thanks for sharing it : ) and I was just wondering if with 2 years of hindsight you didn't noticed any downside.
Thanks!"

 

[mdgm]

One option would be to boot off a Thunderbolt drive.

If you have a Mac with a TB3 port you could connect a TB3 NVMe drive to the TB3 port.

If you have a Mac with a TB1 or TB2 port you could do e.g.
iMac -> TB(1/2) cable -> Apple TB3 to TB2 adapter -> TB3 dock -> TB3 NVMe drive

Even over TB1, a TB3 NVMe drive will outperform a single internal SATA III (6Gbps) SSD.

If you have a Mac with a TB1 or TB2 port and want to use a bus powered TB3 drive then you need a TB3 AC powered dock to provide power to the drive.