It allows me to easily record a wide array of amps and cabs, or just plug the guitar and headphones.
Operation is straightforward, sound quality is top notch and has different possible setups and use cases. Easy recommendation.
Edit: After a few days of playing through the device, I came to the conclusion that the all the goodness in the product, didn't make up for the absence stereo out and an FX loop. Also, although initially it feels convenient to use the app - which is very well made - after a while it starts to feel difficult. I believe having a few more knobs on the device and allowing for a more direct control, would really improve the user experience.