I have previously given a positive review for the Philips SHE3590, a cheap IEM that sounds good.
 
I purchased the Philips SHE3595 because it looks like the SHE3590, has a microphone and it was cheap at Dick Smith's closing down sale (a major Australian retailer).
 
While they look similar, the SHE3595 has a rounded protrusion and doesn't fit so well as the oval protrusion on the SHE3590. The SHE3595 sounds tinny and ragged in comparison to my SHE3590 and AKG K324P IEMs. Why can't an IEM with microphone sound as good as an IEM without mic?

I bought these years ago and honestly haven't used them much. Recently, I have come to appreciate that the AKG K324P IEM headphones give a neutral, realistic sound unlike the many bass-heavy headphones that are popular today. It seems that when the bass is emphasised the mids and highs lose some clarity. Sure, it's easy enough to attenuate the bass but it's not so simple to recover whatever is missing. Good luck in finding non-basshead phones today.

The Philips SHE3590 headphones were listed on the Head-Fi Headphone Buying Guide. They are inexpensive and widely available. Most Australian electronic retailers stock them and they cost about AUD15. I bought these (in white) to replace my lost AKG IEMs (which I have since found again!).
 
Build quality is cheap and plastic looking. Nobody will think to steal these headphones and you won't look like Dr. Dre (Mr. N.W.A., coming Straight Outta Compton, y'all better make way) when wearing them.
 
I gave the SHE3590s a quick listen this evening to a variety of classical, pop and rock music and in comparison to Superlux HD681 (full-sized, open), Xiaomi Piston 3 (IEM for Android phones), AKG K324P (IEM) and Sennheiser MX365 (ear bud) headphones. These are all budget headphones and similarly priced.
 
The SHE3590's sound was surprisingly good. Of course, the SHE3590s do not sound as nice as the full-sized, open Superlux HD681 headphones but IEMs are typically used when small size and isolation are important. Compared to my AKG K324P IEM headphones, the Philips SHE3590s have more bass and, it seems, sounds less realistic. For example, the K324P sounded better for jazz music (Louis and Ella). On the other hand, the SHE3590 sounded better for acid jazz, where they emphasised the beat. The trouble with IEMs is that they often sound different and suit different styles of music. We have to buy them first before deciding whether they are suitable or not.
 
These headphones were a little uncomfortable to wear on my ears: the medium inserts were a bit large and the small ones were leaky.
 
I do recommend these headphones because they are inexpensive, satisfactory and readily available through normal retail outlets.

I wanted to replace the tinny OEM headphones for my Moto G Android phone and several reviews on Head-Fi rave about the Xiaomi Piston 3 headphones. I was aware that there could be fake Xiaomi headphones on ebay and other websites. I bought mine from GearBest.com, which has been suggested by others on Head-Fi to be a reliable seller. They cost USD13.
 
Build quality is superb. I love the cable, however a right angle plug would be less accident prone than the straight plug. Presentation is classy but nobody is going to bother with reusing the case: it takes some trial and error to get the phones in, the controller in and wrap the cable.
 
I gave the Piston 3s a quick listen this evening to a variety of classical, pop and rock music and in comparison to Superlux HD681 (full-sized, open), Philips SHE3590 (IEM) and Sennheiser MX365 (ear bud). These are all budget headphones and similarly priced.
 
Wow, the sound was exciting at first and especially for pop music. However, the Piston 3 sound was not true or detailed in comparison to the Superlux HD681. There was way too much bass. For me, the Philips SHE3590 IEM headphones sounded better. The sound of Piston 3s did NOT improve after "burn-in".
 
I think the strong bass is for commercial reasons. As a teenager, I would routinely switch on "MegaBass" on my Sony Walkmans (remember those?).
 
I will give these headphones away to a teenager who listens to pop music and can't live without their smartphone. They will love them.

I was browsing through a (bogus) fire sale at Dick Smith (Australian electronics retailer) today and spotted Sennheiser MX365 ear buds (white) for AUD8.99. I bought these because I wanted ear buds, because they were inexpensive and because I trusted they were genuine Sennheiser (lots of fakes online).
 
Build quality is cheap but satisfactory. I like the right-angle headphone plug, it does not stick out. The foam covers are not durable (never are) and I threw them away.
 
I gave the Sennheiser MX365s a quick listen this evening to a variety of classical, pop and rock music and in comparison to Superlux HD681 (full-sized, open), Philips SHE3590 (IEM) and Xiaomi Piston 3 (IEM for Android phones). These are all budget headphones and similarly priced. Unfortunately, I had no other ear buds for comparison.
 
The listening experience was pleasant but unexciting. Because the MX365 is an ear bud heaphone, it lacked the warmth and detail of the Philips SHE3590 IEMs. The Superlux HD681s had a much more exciting soundstage than the MX365.
 
I think the MX365 is a good value for an ear bud headphone. Sometimes I don't want the headphone to block out environmental sounds. I would buy these again. However, for listening enjoyment there are better budget headphones in the IEM and full-sized categories. Note that the Head-Fi Headphone Buying Guide doesn't list any ear bud headphones!