In ear? vs. On/over ear? Your experience

I have owned over and on ear headphones from some of the best in  the past.  I am once again in the market and wondered about the in-ear option.   The following are my questions/wonderments...

Do in ear become annoying after some time wearing?
How are they sonically?
Do they compete with the best or simply a different catagory?


I bought a pair of relatively inexpensive NuForce IEMs after reading some favorable reviews.  I bought them for traveling.  

Overall, I am not a big fan of IEMs.  Mine sound fine, but I just can't get comfortable with them inserted into my ear.  I replaced the OEM tips with Comply tips, which I find a bit more comfortable.  However, I really prefer the comfort of a regular headphone, either on-ear or over-ear, for longer listening sessions.

Naturally, this is a matter of personal preference.  I wonder how custom-fit IEMs would feel, but I really don't use IEMs that frequently to make such an investment.
For me, nothing beats the small size and convenience of IEMs. My RHA 750 and Shure 535 sound great. Thinking about some customs....

The often overlooked disadvantage, to me, is that if you're interrupted and have to remove one of them to hear someone,  it takes a few seconds to replace them in the ear afterwards.  As opposed to on-ear or over-ear headphones that are easily placed over the ears. 

Also, people don't always notice the IEMs and will speak without realizing you can't hear them. With headphones, they will wait until you remove them. 
For me over ear always sounds better than in ear.

I went extreme TOTL for in ear set up and just was not satisfied due to limitations of IEMS. Just my opinion but some people love in ears.

IEMs did improve a lot over the years.

I had the u18t, sp2000, and a pw1950 cable. That retails for 7000 together roughly and it didn’t do it for me.

General rule is speakers over headphones over IEMS, but everyone has their own preferences.