That sounds like it might be difficult to sustain, but this kind of hand curation is the surest and easiest way to consistent quality. Thanks for doing it!
You might want to considering billing this as part of the product's description. My biggest question coming in was how the music was selected because I wanted to know if there was some mechanism to avoid genres that I'm sure to hate. I had to come here to find my answer.
I'm looking forward to trying out Jolt tomorrow.