Literally the best and my favorite show.
Jensen Ackles, Jared Padaleki, and Misha Collin's performance was top tier. No unnecessary overflow of emotion or stone cold expressions. Mostly just perfect.
Though, I did notice that the special effects weren't all that good. But, it didn't really matter because the story and plot made up for it. Every episode was always intriguing, especially after 1x2. The second episode of the first season was what really got me hooked on to the rest of the show. The early seasons had this eerie, horror-ish factor that was always fun and suspending (thanks to Eric Kripke), but that eventually went away (not the suspense- I mean the horror). Sometimes I can't even believe that I actually watched 15 whole seasons of a show. Fact is, it was totally worth every second. Filler episodes weren't boring either. The brothers would sometimes stumble upon something they haven't seen before and we'd follow them on an investigation- learning about multiple other supernatural beliefs. Writers also kept it somewhat realistic, like, the Winchesters weren't some *insanely* skilled or overpowered people. Just two brothers with allies and experience (also might be a *little* plot armor but yk).
Anyways, there would be probably more I'd like to cover but I'm tired.
So, overall Supernatural is a 10/10 watch. Good build up to the conflicts and character development was satisfying. Though shows/movies don't surprise me often, this did a few times. 100% recommend. (It can be gory at sometimes fyi)