There were a few panic sales of them after the nerf. It's not vivid, but clear, in
peauction history.
As someone who bought one not long after starting, i was certainly aware of the market feeling about them after the nerf. The bid price dropped to somewhat below what i had paid a year earlier in some activity i observed. Since then i haven't paid much attention, though.
Beyond giving 2 more damage than a106, it is slightly more eco. It's not a large amount, but considering the lengths people go to economize in this game, it's enough to give it premium attraction. In addition, it's the only good energy amp guaranteed to never drop again.