CloudBounce

I can't see where it might be useful. In general, I do not like automatic mastering systems.

Its probably good for beginners in the field but after some training you can quite easily to do the same thing yourself and save money. They don't have even reference track upload feature. Your track will get louder and they will apply some predefined EQ to it.

Paying $10 per song and they don't even do a cloud backup for you. its simply too high for common beat producer.

To make their offer more attractive, I would like to see paid mastering by person where you can get up to 3 variants and chat with mastering engineer. Yes, this would be really useful.