This set in my opinion, should work alright in singles.
However there are some things that you need to know when using it:
It cannot touch the likes of Mega Mawile, so beware.
Sturdy only activates at full HP, no less. So you might like a spinner and/or a wish passer.
Priority will be devastating. Especially when it comes from a Talonflame.
Close Combat makes it's defenses paper thing (if they weren't so already) so give it full investment in speed to outspeed scarfmons.
Set up only when the situation is such. If your Sturdy breaks, then don't bother setting up when your opponent has a fast Pokemon. Keep it as a late game sweeper and/or a Pokemon that can destroy a Pokemon which is out on a sweep.
Salac berry is situational. If you want it activated, keep Sawk at full HP and let it get hit by a strong attack (but not on a switch if possible).
Also, this set is also used by Hitmonlee (or almost, it uses a Liechi Berry instead for attack and Unburden).
Here's a very weird set I've encountered before:
Hitmonlee @Liechi Berry
Nature: Adamant
EVs: 252 Atk / 252 Spe / 4 Def
Ability: Unburden
Moves:
Endure (a replacement for Sturdy)
Stone Edge / Rock Slide
Earthquake
Close Combat
You basically come in on a revenge-kill against a physical sweeper with no priority, and eat a hit (lol) while using Endure to survive. If pulled off right, then when your berry is consumed you get a huge speed boost (Unburden) and a decent attack boost (Liechi Berry).
Hope I helped!