IVY/Haswell is old!
My point is that QLC could STILL outlive those boxes, so why not consider using QLC and spend a bit less money?
And I have QLC in my brand new laptop as primary, secondary and thirdary (is that a word?), for a total of 8 TB in the machine (yeah, I'm a glutton like that), so when they start to go bad, you'll all be the second to know.
In the meantime, I just keep making sure my backups run successfully. My static data (music libraries, 3D graphic libraries, etc) all get backed up monthly with incrementals every other week, while my boot, app, and project drives all get weekly full backups weekly followed by incrementals every 8 hours. Given my backup schedules and my work habits (it's a personal machine not related to my job), my worst impact will realistically be no more than 3 or 4 hours of lost work at any point in time.
With that kind of backup strategy, I can easily run my QLC SSDs all the way to the "dead as a doornail" state. Or at least as long as it takes for me to fill them up with the next orchestral VST library, heh!
But really, if they are old machines, why spend a lot of money on storage media?