First shmup i've ever 1CC'd, and i think it's a really solid one.
The music's awesome (twice, because there's an alt version for every song in the game!), the game looks pretty good too, and i think the game does a really good way at easing shmup newcomers like myself into it. On normal mode, if you get hit while holding bombs, you will autobomb which is really really useful because that means even if you still struggle with timing your bombs to escape death, the game got you covered. You also need to try the game for a while to unlock continues, which i think is really smart, because that means you actually have to try the game before being able to simply use infinite credits to get to the end.

The scoring system is also pretty neat, forcing you to use your subweapon and be pretty aggressive to get more points (and, by extension, more lives), which imo also is good for a newcomer, at least having to be aggressive with the subweapon resonated with me.

On top of that you can try missions to familiarize yourself with the stages, or even play in stage select mode starting from the mini bosses or even bosses to learn their patterns, etc...

All those elements make the game a really good one to start shmups imo, and from what i heard even for shmup veterans the game is really solid on higher difficulties