I don't know of any safety issue with NiMh batts regardless of where they were manufacutured. It's quite practical to use them, however, they are not good at sourcing high currents the way Li-Ions are. It's due to the much higher internal impedance. You pretty much need to stick to higher resistance atomizers with NiMH (3Ω and above). If you try to run an LR atomizer with them, you'll get a lot of voltage sag resulting in lackluster power delivery.
The safety concern with cheap Chinese Li-Ions comes as a result of the bad reputation they get for falsified specs. If they're willing to fudge on that, what else do they fudge on? I haven't heard of anyone specifically that has had an issue with them, but when you can get a battery with a good reputation like the AW for a decent price, why take a chance on something like that. It's just not worth saving a couple dollars.
