Teal or no teal – that’s the question

I’ve been thinking about painting a wall in the living room for a while, so when I saw this I had to share. I’m quite tempted, but I don’t want it to look dark. I do love this shade of teal though. 
photo by Daniella Witte
I already wrote this post about my colour of choice Peacock Blues. Should I use my testerpot on the wall? I’m quite tempted after seeing this photo. The alternative would be to paint a large board of plywood. Hm..
What do you think? YAY or NAY?!