I designed the Venom Stronghold metal battery charging box when I worked there. In the process I blew up many LiPo battery packs including 2S 5000mah, at least 12 packs in one day in the same container at one point.
My point is I know how difficult it can actually be to blow up a LiPo on purpose. I would say that the pack failures and subsequent fires and damage could have been directly related to charger set up error AND lack of supervision. The charger when set to NiMh charge mode can pop a pack but it takes a long time.
In general if your pack has not recharged in about 1 hour at the standard 1C rate then there is an issue of some kind. Being present to check the charging parameters will prevent a catastrophic failure. Most chargers will fault and stop a charge cycle if there is a problem provided it is set to the right mode of charge.
I have not seen, in the millions of packs we sold, a single pack explode during charge due to a defect. Ive always seen packs fail due to misuse and incorrect charger set up.

Also the one great benefit to a LiPo pack is its early warning by ballooning BEFORE bursting open.
In most cases Ive seen or purposely caused failure in metal round cells there is very little warning before a catastrophic event. When a NiMh cell explodes its literally a grenade sending shrapnel flying at high velocity outward followed by material on fire.
Ive seen cases of misuse and mishandling resulting in the loss of an eye and/or property damage.

I prefer LiFe or LiPo for my models and Ive been testing this for over 4 years straight in nitro, edf and jet models.

MAKE SURE YOUR CHARGER SETTINGS MATCH YOUR PACK BEFORE YOU PRESS START!
DO NOT STORE YOUR LITHIUM PACKS FULLY CHARGED FOR A PERIOD LONGER THAN A WEEK
DO NOT CHARGE ANY BATTERY PACK IN YOUR MODEL