Tested on: Sony Walkman NW-A55, SoundBlaster Creative G5 and direct connection to various devices.

Pretty much everytime I asked for a recommendation of IEM that can isolate, I've been recommend Etymotic and Moondrop Blessing 2. Now, I haven't tried them personally but I did research this topic and the differences, and I've also tried the famous "Christmas tree tips" on Etymotic.. which should be called "alien huggers". I'm comfortable with using ear plugs nowadays but I found the triple flange tips extremely uncomfortable to use. Sound-wise, I skipped on Etymotic based on people saying that it doesn't have good bass and the sound is very flat, 2D, overly analytical.
Shure is not getting a good reputation nowadays but the Aonic line is actually quite good. Aonic 3 and 4 in particular received very good reviews from crinacle, with both 3 and 4 scoring a B.

The best thing about Shure Aonic 4 for me is that it manages to deliver rich, expressive highs and treble without ever piercing your ears on high volume. I listen to music on Walkman NW-A55 and if you do get these earbuds, NW-A55 is a very good choice of a portable music player for them.
Mids and lows are good, as well. Bass is present and if you use EQ, you can add more of it.

After testing different tips, I found that the yellow foam sounds the best with gray tips being the shoutiest and black foam being the most boring and simply condensed. Be careful when replacing the tips because unfortunately plastic shells seem flimsy. They won't break easily but if you aren't careful, it's possible. Use included tools to remove tips at all times.

Speaking of comfort, I do not have any issues listening to these for long periods of time. My ears do not get sweaty despite currently being in very hot environment with poor A/C.
I highly recommend to upgrade the cable to EAC64CLS or the 46 inch version of it. It's just much more comfortable to use and does not have the annoying remote controls of stock cable.

I've tested beyerdynamic DT 880, Sennheiser 560s, Sony MDR-1AM2, Shure SE215, Sony WH-1000XM4 and the sound was the most enjoyable on Shure Aonic 4. DT 880 worked best for the classical music and had a good imaging (being open-back) but was rather difficult to listen to in many other genres and barely usable for gaming (!). Sennheiser 560s had great imaging and soundstage but I absolutely hated the mid-forward sound signature. Sony MDR-1AM2 was incredibly disappointing as it sounded poorly balanced, overly warm but also very harsh in highs. I pretty much gave up testing 1AM2 when I heard how piercing it sounded... and people say beyerdynamic is bad, hah. WH-1000XM4 was enjoyable but nowhere near as good in terms of pure sound quality, I think they are largely intended to be travel "classy" equipment rather than "as good as you can get for the money".

I have beyerdynamic TYGR300 R coming in soon, getting it for gaming so if anyone's interested in comparison, feel free to message me.

I highly recommend everyone to check out the Aonic line of IEM. It seems like Aonic 5 did not turn out good despite having more technical capabilities. I have not tried them but would be really interested to hear comparison from those who did. Aonic 3 is the 'entry" level with Aonic 4 being the best choice in this line.
If you need isolation but don't want to compromise the sound quality, if you need IEM that can do different genres and gaming, these are the best choice in the price range.