Yes and no
From a fit point of view, it is personal. If you get into IEMs not everybody can adjust to tips inside their ear canal
From a style point of view it is obviously subjective. I freely admit it is one of the reasons I picked up the AT ESW9s
From an SQ point of view it depends entirely on a particular model depending on your budget, music tastes and source. IEMs can get very good if you lay down the money and my UM2s were certainly the best thing I had listened to for the best part of 2 years. Then I picked up ESW9s and I am back in the full sized headphone camp and looking to pick up a second one