How many people have upgraded the S4 firmware to: initramfs.bin.SD-20141016.tar.gz from the bitmain website?
I only ask because mine is still running on the factory firmware no problem with difficulty manually set, so I'm kind of wondering if I should bother with the upgrade.
I don't think you'll be able to get an accurate number of people

Even if you don't currently have any problems you might have issues if you ever want to switch pools. I had trouble with some rentals - for some reason even December delivery S4s came with old firmware - upgraded to the 1016 version and haven't seen any problems since.
I really only asked because I've been seeing people have more problems after upgrading the firmware (not necessarily with the S4, but with S3's for sure), and I've kind of been taking the "If it isn't broke don't fix it" position with my miners.
I hear you. I haven't touched my S3s since July-August. The latest S3 upgrade (November something) seems to be borked. The 1016 S4 upgrade is fine and highly recommended because of the issues with low starting difficulties.
Okay so I finally got around to trying to upgrade the firmware on my S4. I've downloaded the initramfs.bin.SD-20141016.tar.gz file, and hit flash. I see that it uploads to 100%, but then after that, my connection times out and the miner does a factory reset.
I re-downloaded the file and tried numerous times, same result every time. Anyone else have this issue, or have any suggestions?
I would try a different Micro SD memory card. First, you will have to put the base image on the new card.