Please allow me to blow off some steam here.
I own four Carvin/Kiesel guitars. Two DC127's, a DN612 Double Neck, and a Vader. I've been playing them as my main guitar since 1992. But the company's quality and especially customer service, despite appearances, has gone to crap.
One example; I recently ordered a pair of H22 Holdsworth 22-pole humbuckers. The coil wiring and/or internal construction did not match the Carvin standard (I have successfully installed other H22, M22, C22, and Lithium pickups). They behaved, sounded, and tested wrong no matter how they were wired (and I am very experienced at this). My inquiries to Kiesel about the proper wiring, or the possibility of assembly error, of these H22's went unanswered. No reply. None. The pickups are in a drawer, where they will remain indefinitely.
I also recently ordered a Vader with a $400 top to be hand-selected and fit by Jeff Kiesel. I sent in pictures of the type and direction of flame I wanted. What I received was exactly what I explicitly told them I did NOT want. Since it took 12 weeks to build, and I needed the guitar to pay the bills, I kept it.
Now, the lock nut on the headless Vader is proving to be garbage. They use the ancient design, first adopted then abandoned by Kahler, where an Allen screw insert rotates directly onto the string, acting as an effective string cutter. The line between the Allen screw holding or cutting is a very fine one. You must be very very careful to screw it down hard enough, but not too hard.
Now, the nut won't hold the unwound strings. They just slip through the Allen screws no matter how hard you tighten them. This design is an abomination and should never be used on any guitar, let alone a $2000 guitar. It is a joke. Kiesel has yet offered no reply, let alone useful help. I replaced it with a $4 Chinese part from Aliexpress that has a much better design. The quality of the metal is poor, but at least the design securely holds the strings without breaking them.
I've loved and used Carvin guitars for many decades. But I'm afraid I have to say goodbye. Their customer service is a disgrace compared to what it once was. The first problem I ever had was with a 1990's double neck. Mark Kiesel called me personally to resolve the problem. That was then. This is now, and now sucks.
I'm sure dozens, if not hundreds, of you have nothing but glowing things to say about them. I was once like you, and I understand where you are coming from. I wish I could still be there with you.