Depends on the PSU you use.
If you need a beefy PSU, I suggest the Meanwell RT-125, if not, the RT-85 is just fine. Both have pots for voltage adjustment.
I suggest reading the manual which should address any technical questions you have:
https://rgbslab.com/pages/has-instruction-manual
There's also this thread with lots more info:
https://www.arcade-projects.com/threads/home-arcade-system.332/
As a rule of thumb, the Superguns from Aliexpress are "potentially" risky.
Don't risk your expensive arcade boards with dodgy 12v Laptop power supplies that are often included with these units.
The HAS is highly regarded by the arcade community and considered the top-of-the-line in Supergun technology and safety. Tried, tested and trusted.
I haven't used one, but the Minigun is also another alternative that is very popular. It's less feature rich, but its price point may suit you better if you're on a budget?
The build quality and components used on the Minigun vary depending on who's doing the build. However, there's some trusted people who make these on here such as
@jcmorrisii,
@Big_P Big_p, etc.