My experience with Amytek CS is that they never reply to emails whether it is a presale question or after sales warranty. I was able to get quick response from them through Facebook message though. They replaced my Prime A2 Pro and gave me options for additional freebies to choose from. The CS was actually really good if you contact them through facebook PM. I’m a big fan of AT light design and finish. Feels very premium but rugged. Driver efficiency and regulation is above average.