BlackFire One Step review on black car
 

Black car with swirl marks and very stubborn hard water stains since purchase, which I was unable to move by hand polishing. I had considered getting a professional detail, but I don't like to pay people to do things I should be able to do myself.
I read about this product online and decided it was my best bet.
After a gentle bucket wash and quick claying, I used BlackFire One Step polish/sealer with a random orbital buffer and polish pad and got great results.
Paint is deep black and almost blemish-free, with complete removal of the water stains.
Supposedly pretty gentle abrasive properties on paint, so a light polish with less worries of burn through. Plus a long lasting sealant.
Not sure if supposed to wax afterwards, but I didn't.
The nicest part is that it is dust free on removal, final wipe is comparatively easy.
$40 but worth it IMO, good stuff. Forgot to take before and after pics but can find them online.
I recommend it for amateur paint correction for those who want to do it themselves.

Dave,
Glad you got the swirls and spots out, i have almost the same situation. I have a Black '19 GS ( 250 mi. ) with some swirls and water spots and will be doing the same soon. I read and asked questions. I purchased the G 21 and Blackfire AIO a short while ago and will be going at it some time soon. I will give it a coat of Jescar power lock and sealant and after that in time collinate # 845 insulator wax.
Good job !
I will also first foam cannon ,clay it and paint prep it prior to buffing.
Anyone find that these products will work together nicely?
Sounds like you did a great job!!
Rich

Black Fire has several excellent products with One Step being one of them. It's an "All-In-One" (AIO) product and handles light swirls and water spots well.

Yes, you can definitely wax over the top of it. Do you have to? No --> I suggest you do as AIO products are by default not a pure wax so they don't do as good as job as a pure wax.

Yes, Black Fire's AIO and Jescar Power Lock (which is a sealant) will work fine together. BTW: Jescar is the US distribution of Mezerna for those familiar with that line of products (EXCELLENT!)

Thanks for the vote of confidence. After the sealant I will use a wax.( after reading instructions on the sealant of how long after applying the sealant to apply the collinate wax.
Rich