Penned Tiger 2 UFP almost 2km away the other day, usually goes through and destroys the engine, very rare if real example at all. Take it from person who has 1.5k+ kills in Conq and naturally earned ace crew.
100mm at 60o is enough for APDS to pen UFP of tiger 2 whereas 100mm at 60o pen AP cannot, because APDS has much better 40-50o modifiers that you cannot see, because of this, the Conq can pen the upper hull of the tiger 2 over 2km away.
Shattering rarely if ever occurs on homogenous armor, it only impacts spacing or for some reason 2 plates sandwiched together (this is the real ahistorical issue, 1mm of air shouldnt cause a round to lose all its pen)
Also if APDS keeps shattering when it pens then why isnt that represented in the damage model, that sounds like extra damage to crew if you ask me, and its a very hard and sharp material going at supersonic speed.
I will still chose APDS over AP in most situations as solid shot has no real advantages over (gAy)PHE whereas APDS has distinct advantages in its historic bracket such as very good ricochet angles and velocity.
Regarding shattering of the gen 3 APDS it shouldnt be happening at all and Gaijin said that themselves. I dont play those vehicles much because they are overtiered, but I havent witnessed it personally.
Besides I have sekrit document of Chieftain APDS testing this specific shattery scenario and it showed the round capable of penetrating several spaced plates at a 65o angle.
EDIT:
Document shows that the round can penetrate at least 105mm of very air spaced armor at 60o at 1000 yards, so this round should not be shattering by any metric at all, unless Gaijin intend to make it so that other rounds like AP can shatter under circumstances more stressful than that (examples of AP shattering such as the Maus experimental round and american US M62 shot in ww2)
Also HESH able to penetrate 600mm of reinforced concrete but unable to blast through 15mm of RHA with the HE content…