Do IEMs scale with headphones at the same price range?

[Dasaesthetics]

let's ignore the kings of price/cost ratios such as takstars and superlux. Will a $100 IEM sound similar, worse, or better than a headphone (open, closed, semi open and closed) at that same price point?

Looking for something warm under $150. Bought 3 pairs of over the ears online, returned them a few days later thought id give iems a try.

 

[Me x3]

Depends a lot on the headphones involved and personal likings!
 
Good IEMs (such as the Yamaha EPH-100) can easily compete with some closed back headphones priced 200, but at the end of the day, IEMs are not full size headphones and viceversa, the experience is always a bit different.

 

[IboHD800]

From my experience, headphones (Beats aside) are almost always better in terms of SQM (sound quality to money ratios) comparing to IEMs. 
 
For examples, my Fidue A83 (@ US$ 219), although excellent in vfm with euphoric mids, is inferior to the AKG 271 MkII (similar MSRP but much cheaper street price) in both details and sound stage. Similarly, my ATH-2000X outperform the Sony EX-1000 (again, similarly priced) in almost all aspects, considering both require proper amping (I am using the G109 for the 2000X and RSA Shadow for the EKX, again similarly priced).
 
In terms of the $100 bracket, I still believe there are more choices for headphones than IEMs. However, the portability issue and superior isolation make IEMs the more popular choice for outdoor listening naturally.