I was tangentially involved in a project that invested quite heavily in developing a device based on Edison. I don't recall hearing about any hardware problems you describe. In fact, I remember being surprised at how easy it was to setup the flashing tools on my computer (those might have been some in-house developed scripts though). What was a significant hurdle in development was Intel's lack of support and the outdated kernel in their distro.

I think when it came out Edison was quite nice. You got wireless, flash and a decent CPU in a very small package. The only really bad thing from the hobbyist perspective was the fine-pitch connector that was impossible to solder by hand. It made any DIY project completely dependent on Intel's expensive break-out boards. Yocto Linux also seemed more oriented towards serious products than random hacking (especially the "build a firmware image" approach vs. Raspberry Pi's "ssh in and apt-get stuff")