Voted by choice 50/50. But if you had that poll before last year, before I acquired my first pair of IEM (Truhear Zero Blue) it would have been loudspeaker 90% or more. I had many pair of headphones in the past, some of them highly praise by audiophiles here, but I only ever used them because I had to but never as a first choice.
Since my first IEM, I have 3 now, I have fallen in love with how the music come trough.
Not instantly, to me , it was a learning curve. I had to learn getting comfortable, getting the proper seal. But now, about a year later, I often choose the IEM over the speakers. I still have my fully dedicated music room and my semi dedicated (more isolated) room, for when people are still resting, both with a nice speaker set up and dedicated, well positioned, comfortable seat. The difference is that now, I also use those seat to listen with IEM.
I appreciate both experience, I would not want to have to choose.