Wow! What sort of machines are these? Mine are optical disc free since 2012. That's almost 7 years now. I used to hate using them. Slow, noisy and fail within 2 years. Every single one of them regardless of brand.
They are nearly all workstations bought cheaply on Ebay with no HDDs, OS etc and then re-built to my own desires.
Includes HP Z600 and my latest is a Z800 which I bought with 96GB RAM and twin CPUs (the fastest ones - Xeon 2690).
And the Z600s and Z800 kick the crap out of most i7s - 12 cores beat 4 cores almost every time!
The Z800 is a real BEAST - about 1610 on Cinebench when on full power.
The only problem with these machines is the fans - they don't ramp up when the CPUs get hot - so I use SpeedFan which has to be specially tied in to every processor (all 12 of them) - but now works fine.
Have also got 4 Samsung 960 SSDs (3x500GB and 1TB) in RAID 0 which gives me a 2TB SSD running about 950mb/Sec.
The extra 500GB left on the 1TB SSd is running in Samsung's RAPID mode which uses about 4GB RAM as a cache which gives it a nominal speed of about 2.5Gb/Sec.
I usually run a 48GB RamDrive when editing pics (about 3.5GB/Sec)
And the OS is on another SSD on a PCIe card running about 400Mb/Sec.
And it also has THREE DVD bays - 1 fitted with a DVD ROM and 2 DVD re-writers - so some of us still use them!