That said, like with most IEMs, sleeves should be replaced sometimes (probably once a month or if you get any dirt on them—be careful with handling and don’t let that stuff get into your ear canal), so that should be factored in the price.

Which sleeves you choose makes a big difference—they are more or less the noise isolation part of IEMs, and they make or break your comfort when wearing. I swear by the combination of SE215 + Shure’s original black foam sleeves (or, if those cannot be obtained, Westone’s foam eartips). Passive noise isolation in this setup is better than ANC in AirPods Pro for me subjectively (although according to rtings.com’s measurements they go head to head), and is easy to wear for long periods of time.

(I guess I’m replying to thepostoffice but for the most part this is addressed to dghughes’s upstream post.)