As with all value special effects lens filters, this isn't going to be for top optical quality. It's for when the special effects will enhance the overall picture so that doesn't matter.

That means you have to experiment and think about your use case, because it's not going to work well in a lot of situations. You need point light sources, often in otherwise dark or dim environments.

There's a prismatic (color-separating) effect I wasn't expecting in the starburst lines. It's welcome, though.

It's pretty easy to twist the outer part of the filter to go from aligned to crossed filter lines, for 4- or 8-pointed starbursts. If there are a lot of lights or they're close together, 8-pointed starbursts will probably be overwhelming. That's where I see the value in being able to switch it up on the fly.

I also recommend experimenting with your camera settings to see when you get banding of the starbursts and when you don't. I took quick sample pics with my cellphone, so they're not representative of what you can do.

I quite like filters like this for the right purpose; I plan to use this one when there are fairy or holiday lights in the background or foreground (behind or in front of my subject).