I am not a mech fan, I own two, but very seldom use them. If you are not sub-ohming I don't see why you'd want one.
Are mechs safe?
Dynamite is safe if stored and used correctly
Proper batteries and build should prevent explosions
Batteries:
The battery must fit your build. Using Ohm's Law to select batteries that can provide Continuous Current of 50% greater than you atomizer requires. Ex I=V/R 4.2V (voltage of a fully charged battery)/ .8 ohms (the resistance of your tank) = 5.25 amps. So your minimum battery would be 10.5 amps.
Do Not Use ICR or Protected batteries.
If the manufactured name has Fire in it run don't walk away
Samsung, Panasonic, AW, Efest, Sony are good battery brands.
Be Careful Out There
The above does not take into account a possible short which could cause injury and damage property.