Hello -
I’ve been using a second gen Drobo for years with only occasional minor issues. My only compliant would be slow transfer speeds, even using the FW800 connection.
I’ve been considering upgrading to a 5N/D, mostly for the extra storage bay. I currently have 3TBX4 and am beginning to add 4TB drives due to space needs.
Besides the extra bay, are there any other advantages, such as speed, to recommend going with a 5N/D? My Mac does not have thunderbolt, so I would be stuck using USB (2.0 because of the older MacPro3,1) with the 5D - but would be faster with ethernet on the 5N.
Thoughts? Thanks -
Speed, speed, speed, and more speed. The old Drobo’s were doing well to push 15-20MB/sec. The 5N can push over 100MB/sec, and I believe the 5D pushes twice that.
If you switch to a 5N, be aware that you can’t migrate the disk pack directly, and there are subtle differences when accessing data on a network share as opposed to a direct-attached disk.
I moved my 4x2TB Gen2 diskpack to a Drobo 5D.
The speed increase was phenomenal.
Over the last year, I have replaced all the original drives with 4TB WD Reds and populated the Gen2 for use with Time Machine.
The flexibility Drobo offers is fantastic.
You don’t have any PCI slots open in your MacPro? You could add a USB3 card which would give you 100MB/sec with a 5D.
Thanks for the input! That’s what I was looking to hear 
I believe I still have one remaining PCI slot open for USB3 since it sounds like that might be a easier transition.
Best -