It works very well if correctly sanded and has some benefits that you can't get with a regular mat finish.
1st. Given time most mat finishes look like hell. With this technique you have real UV protection and can re-sand with 3000, 4000 or whatever to renew the finish.
2nd. If you get tired of the satin, you can buff and polish it out to gloss black.
One more hint. If you like Black, never have Black mixed. Just buy black mixing base in the brand you want. This will save you a butt load of money.
