I've seen Daisy before but never tested it personally. Looks like a nice board, and if it covers what you need, go for the more economical option!

For me, it comes down to convenience and connectivity. Sonatino has WiFi, BLE, a built-in 3.5mm jack, integrated amplifier (for a small external speaker), and battery charging. I was building some toys and interactive audio/art projects (example: https://hackaday.io/project/191186-sax-a-boom-clone ), and Sonatino made it really quick to get up and running.