Comparing MSs, DG, and MBD:
Assuming no other traits and no mods.
Assuming no enemy armor.
Assuming all shots connect.
DG, Two Pistols, Avg DPS --
SoG 2: 19.7
SoG 3: 33.0
SoG 4: 75.0
SoG 5: 166.7
MSs, Pistol, DPS --
SoG 2: (16.7)
SoG 3: 27.5
SoG 4: 60.0
SoG 5: 130.0
Bullet Dance makes these numbers go insane:
MBD, TH 2, Two Pistols, Avg DPS:
SoG 2: 58.3
SoG 3: 100.0
SoG 4: 225.0
SoG 5: 500.0
and TH 1 actually provides BETTER benefits (until SoG 5) due to a bug:
MBD, TH 1, Two Pistols, Avg DPS:
SoG 2: 77.8
SoG 3: 133.3
SoG 4: 300.0
SoG 5: 400.0
Edit: Hehehe, get this: I didn't count in the extra 2 damage from SoB (to get TH), so the actual values will actually be HIGHER than that!! See below!
MBD, TH 2, Two Pistols, Avg DPS (with SoB 2 bonus) --
SoG 2: 75.0
SoG 3: 125.0
SoG 4: 275.0
SoG 5: 600.0
MBD, TH 1, Two Pistols, Avg DPS (with SoB 2 bonus) --
SoG 2: 100.0
SoG 3: 166.7
SoG 4: 366.7
SoG 5: 480.0