I am a gigging musician and this system was preinstalled in my main gigging guitar which I purchased 6 years ago. I recently had some noise problems and reduced signal level from my guitar. Usually this is caused by ware on the Jack socket, but with it being a sealed unit and with the special PCB connector for the preamp on the other end of the cable, I was unable investigate or replace with a standard part. Not being 100% sure this was the cause, and not wanting to replace the entire guitar, I decided to replace the whole shadow system for the same one. Features and sound-wise I couldn't be happier with the Shadow system currently in the guitar, it sounds really great and the built in tuner is invaluable.
Upon receiving the new system from Thomas, I immediately noticed some small differences with the preamp unit. The plastic felt cheaper, it seemed lighter and the feel / movement of the rotary knobs aren't as nice / positive as the old unit. After installing the new system, I noticed my top E was a much lower volume. Note that this system has 6 separate channels - 1 for each string. I first thought this most likely the under-saddle pickup with a dead segment. I stripped the guitar down a couple of times again and swapped out the components one at a time with the old ones as a process of elimination. It turns out the fault is with the new preamp unit. My old jack socket was indeed the original problem. I have now salvaged my beloved guitar with a combination of old shadow parts and new ones, therefore I haven't returned the product to Thomann. However, I would have been really upset if I bought this unit for a new install in a guitar.. especially since you need to cut a hole in the top for the preamp. I suspect that Shadow have economised on Production over the years to maximise profit, cheaper materials, PCB etc and clearly the Quality Control isn't protecting the consumer. A real shame to loose the edge by skimping on quality, because the design and sound of the system is really good.