synphul :
Think of es as a 'beta' cpu. Nothing is guaranteed to work properly, there's no warranty of any kind, they're illegal to own/sell. It may not mean much until someone ends up being on the wrong side of intel's legal team. Not sure why someone wants to buy something they call trash.
Even without the whole es controversy unless someone has a specific need for 16 cores in most common applications it's going to be a turd. The speed is 2ghz to 2.5ghz (according to the listing) when the official 2683v4 features speeds from 2.1ghz to 3ghz. A quad core 7700k costs less and will outperform it in most tasks. A similarly priced brand new with warranty broadwell-e 6850k with a speed of 3.6ghz to 3.8ghz (and can be overclocked further) would outperform that xeon in most tasks.
Two things affect processor performance, ipc and core speed. Amd's fx cpu's with their 8 cores fall behind intel cpu's with half the core count repeatedly despite having higher clock speeds because they have low ipc. While the xeon in question has higher ipc it's gimped by low clock speeds, potato potahto. Low core performance and high core count has already been witnessed in most day to day programs and falls behind. If the es cpu ends up glitching you'll have bought a $550 paperweight instead of potentially spending the same or over $100 less on a 6800k or 6850k.
I called them trash because
they are overpriced like 6950x , and like nvidias m/p 5000 quadros
they cost 2500 and can do same as titan X - only thing that makes quadro work better is the driver
but of course you can't install quadro accelerator driven on GTX card , it has hardware lock inside
one dude from russia did that trick and made GTX work like quadro , after that Nvidia changed their behavior in defense frontline and now you can't do that even with hardware surgery
the only thing that Xeons have against i7 is the ability to use multiple CPUs in one rig
avoiding RAM GPU and HDD purchase for each unit
if there were no AMD on the market they would cost even more
amd is a salvation in terms of price policy of intel and Nvidia