Hi it's Alto.
This is a really interesting setup which involves stunning cops either from hacker ecm stun, fire from your DB shotty, or poison from your tombstone shotty. This build also uses dire need which further adds to the stun chance.
This all means that as long as you are engaging an enemy, he won't be able to fire at you.
Yes, even dozers. However take note that the only thing able to stun dozers is the hacker ecm stun.

These are just some video demonstrations of the build in action and how i built it.
This build was strong enough to get me comfortably through henry's rock, one of the hardest heists in payday to date.
https://www.youtube.com/watch?v=fUt0lVIl6Fs
https://www.youtube.com/watch?v=KgM-FXwZGes

Loadout
Raven shotgun:
- Dragons breath rounds
- Short barrel
- Concealment boost
- Compact laser module
- Flip up sight

Locomotive shotgun:
- Tombstone slugs
- The silent killer suppressor
- Concealment boost
- Compact laser module
- Straight grip
- Extended mag
- Riktpunkt magnifier gadget
- Compact profile sight
- Tactical shorty stock
- Shell rack

Deployable:
First aid kits

Melee:
Kunai knife for even more poison stun

Throwable:
Hacker pocket ecm

Perk deck:
Hacker

First aid kits were used to keep you and your team alive, but a different deployable can be chosen if desired. Just make sure to add skill points for it.

Hostage taker is used to boost hackers health regen a bit.

No overkill for shotguns because the poison shotty kills cops in 1 shot. The DB shotty may take a couple shots but it will be very hard to trigger overkill anyway since only the initial shot counts.

Drill skills can be specced elsewhere if desired, these were spare points.

Since the build can get <5 concealment basic SB and low blow can be utilised.

Ace high value target and bloodthirst help for dealing with dozers.