Yep, lipos can be dangerous!
I did Nicad years and years ago, when i was into RC cars ( 1980's). Then i went to NiMH. then moved on to Life or A123.
Had one bad experience with the Fromeco batteries. and since then, i went to Li ions. Liked them, but like you have mentioned, long charge time, and with the 40%ers, i would see voltage drop significantly with snaps, etc...
then i went to Lipos, TP, and have never looked back.
Have yet to have a Lipo problem, but, it can always happen.
The most dangerous, I believe, are the LiPO batteries.
I do not keep any inside my home or garage,
They are kept inside my trailer.
My charge station is also inside the trailer, there is a solar panel on top, connected to a deep cycle marine battery.
I also use the Cell-Pro 8 lab charger. Seems to be a smart charger. Anyways, my 2 cents.