Creality are interesting because they do indeed give you a lot of machine for the money but the quality control is often not great. There are some general dangers involved when using a 3D printer because it has a heating element that draws a lot of current. I've only heard of a few fires caused by 3D printers, but there are true stories of them out there. I know some people who have CR10s and love them and honestly my Monoprice doesn't have the greatest QC either.
There are also very robust machines that cost a lot more for smaller build volumes, but they're backed by well-known corporations and probably tested to Consumer Safety standards. Dremel has a 3D printer that they sell that's basically a RepRap clone.
I will say, when your 3D printer is working, it feels like magic or a (slow) Replicator from Star Trek. But when things go wonky on them it's incredibly fucking frustrating. They haven't really reached the point of being like an appliance. There's always a chance that something gets messed up on your machine (clogged nozzle, bed gets warped or out of level, extruder gears stripping) then you'll feel like chucking the whole thing in the garbage.