I am not forgeting. I just assume that the body armor + extra 2 models and smoke grenade compensate for that. Am I wrong?
To put it bluntly, yes.
Shocks body armor is about equal to -33% received accuracy against weapons with penetration values of 1 (SMGs, Infantry rifles) and less against weapons with more than 1 penetration (HMGs, LMGs, Vehicle mounted MGs). Obers have a base -30% received accuracy.
Now vet, Shocks get one survivability boost of -29% received accuracy. Obers get two -29% modifiers. So each Ober model is ~29% more survivable (give or take a little bit) than a Shock Model (with Shocks being vet 3 and Obers being vet 4).
Then damage. When a shock model dies the squad loses a flat 1/6 of its damage. With Obers about 70% of the damage (at long range) is on the LMG model. Meaning the Ober squad will put out most of its effective damage with only one model left. The ratio of LMG/Rifle damage for obers of course shifts more towards the rifles as range decreases, but even at close range the LMG model does almost as much damage as a Shock model. Obers also deal good damage at all ranges, while Shocks do basically 0 until they hit range 10. This means a player can retreat before Shocks can really do any damage.
Obers also gain the ability to suppress infantry at vet 4, further skewing any infantry combat in their favor. They gain sprint at vet 5, which doesn't help them directly in combat but does have tactical advantages.
Oh and Obers also have a smoke grenade, that slows+damages unit caught in it (gain the ability at vet 1)