Here are some of the mechanical issues I've experience with my EU5.
The bass itself:
- can't adjust magnetic pickup height without removing all strings and the back cover, because the holes for the pickups were drilled too small.
- have to loosen at least 2 strings to get at the battery compartment.
- batteries fit so snugly you can't extract them with your fingers
The stand:
- The screw and rubber gasket assembly cannot be tightened adequately to prevent slippage. For awhile I the bass at about a 15 degree angle, and if left overnight in the stand, regardless of how much torque I applied to the screw, it would slip and I would find the bass rotated with headstock on floor. I have a nice divot in my headstock because of this.
The endpin:
- The hip bolster is of a fixed length, the radius of the bolster is also fixed for some other humanoid species. I'd like an adjustable arm, so that I could get the bass an inch or two further away.
- The hex screw that allows the part of the bolster that touches your body to rotate cannot be tightened adequately to eliminate wobble. Seems to be of cheap metal, so that no matter what you do, it loosens after a few minutes of playing.
The endpin stand adapter:
- The wood and aluminum boot rattles itself off the stand. I resorted to duct tape.
I think the concave shape of the EU5 is brilliant. The composite construction and the piezo pickups yield a compelling tone. Its too bad the mechanical stuff is so third rate. And then there is the disgraceful gig bag ...
I have a love/hate relationship with my EU5, as despite my frustration with the issues above, I don't see myself replacing it with another EUB anytime soon. Nothing and nobody is perfect, but NSD really needs to get its act together. E.g. I had to exchange a bunch of emails with them to inform them that their website had the manual for CR series for the EU series and that the control layout was different.