Shozy Alien owner here. This is a very interesting DAP - it provides outstanding music quality at its price, but the navigation is not very convenient given the lack of screen. Despite the inconvenience, I still had to buy it after demoing. Yes - the sound is that good.
I wouldn't recommend putting a large SD card into it - a 4GB or 8GB card will do. It starts playing in 10-15 seconds after you press the middle button (a bit slow startup), but then is smooth once it starts playing. Pressing the middle button again would turn off the player - not pause.
You navigate through the music through the previous and next button (it starts playing music in the root folder of the SD card, one by one, and always starts from the first song, at a rather high volume (don't put your earphones in before you can adjust the volume ...) To navigate through folders, long press the previous and next button. You will gradually come to realize that you should only bring your favourite music using this DAP - because you have to go through songs in the folder one by one, click after click.
Don't expect to drive huge headphones with it - may be portable headphones under 100 ohm, but IEMs are more suitable. Good dynamics and bass, average soundstage, clear but not very detailed. A rather enjoyable sound. Drives some of my IEMs better than Fiio X5.
No battery indicator - will stop playing once the battery is depleted. Cannot play a few of my FLACs - not sure why (encoding problem?), but this seldom happens. Only supports 24/96 at most.
Good for listeners who are looking for good sound quality at an affordable price, if you don't mind about the navigation problem.