Not surprised by all the PBC love, it’s a great offensive unit and fills a vital roll in our army for which we do not have many options. If I may play Devils (or should I say Deamon’s) Advocate, I have a serious issue with the PBC; its keywords.
The PBC is a Deamon Engine. However, unlike all other Chaos legion Deamon Engines, including our own, it does not have a melee weapon or improved WS. In this regard, the PBC a Ranged only threat, whereas all other Deamon Engines are multi-threat.
It lacks the Machine Spirit keyword. Every 9th edition army has a stratagem to overcome degrading BS on their heavy vehicles. The Death guard strat does not work on the PBC.
No Smokescreen, almost every 9th army has a way to give a vehicle -1 to hit. The Death Guard strat does not work on the PBC.
No Bubonic Astartes keyword. Unlike the Thousand Sons who’s legion traits affect TS Units, the PBC lacks the Bubonic Astartes keyword and therefore doesn’t benefit from the Death Guard’s Inexorable Advance, nor does it help score Despoiled Ground, despite being an excellent unit for holding our home objectives (and consistent with the fluff, ie PBC’s holding the rear while our infantry advance).
To recap, the PBC is a hybrid Deamon Engine / Tank. It gains the 5++ save and disgustingly resilient, but doesn’t gain any melee capability. Despite being a tank, It doesn’t benefit from any of the common stratagems to ignore degrading BS or add a -1 to hit smokescreen buff that (to the best of my knowledge) is available to every other 9th edition army.
When out codex first came out, I assumed the lack of these keywords was a balancing edit, as they felt the PBC was already very strong with DR and a 5++ save. However as more 9th edition codex’s drop that give out -1 damage and 5++ saves like its Christmas, I am less confident that the lack of these keywords was a purposeful decision rather than just poor design.