The accounts of ciga-likes blowing up in people's faces is more or less a tempest in a teapot because people are already wary of them due to their association with smoking. The Li batteries in them are, from what I can tell, no more or less prone to failure than the Li batteries in any other devices - including cell-phones and laptops. Hoverboards had a similar bullshit over-reaction recently as I'm sure you remember, although a bit more understandable considering just how much energy all those cells are capable of storing makes them fail much more spectacularly.
So long as you have the original chargers (you'll probably need them anyhow, since I don't think there are any universal chargers due to proprietary threading), they should be fine. I might avoid plugging them into a PC or Laptop USB port, because on some of the cheaper ones, I've heard, some of the safety features might be located in the AC base rather than the USB dongle.