My company (strobedata.com) has been supplying many ESI users with an "updated" PDP-11 platform called the Osprey Co-processor. The product can run about 4 times faster that the PDP-11/93,4, but most ESI users have been limited to only about 30% throughput improvements by timing constraints inherent in the original ESI hardware and software design.
We can also provide modern upgrades/replacements for the entire HP1000 product series and most Data General Nova and 16-bit Eclipse systems if anyone has an interest.
Sold quite a few disk sub-systems to Dick Jensen of ATEX back in my earlier days in the industry.
