Which is best RDA OR SUBOHM

I just want to ask is rda are safe to smoke i smoke from last 9 years only use subohm tanks yesterday i buy rda tank but now im little bit scared because when i smoke i see the wire goes red and comes out thats the thing i was scared from. Please tell me is there any issues with rda or not and are they safe to smoke.

Original source: https://www.e-cigarette-forum.com/threads/which-is-best-rda-or-subohm.957161/