the t.bone IEM 75

I've only used this for rehearsals. Because this is my firs IEM ever, I have nothing to compare with. But it does what it promises to do without perfectly. Sure, the audio quality is slightly worse than being wired into the mixer, i.e dynamic range, clarity and light noises, but that's a price that I'm more than willing to pay to let the entire band hear click and backtracks. The quality is absolutely sufficient and I'm very happy with the audio being stereo.
The transmitter is a light and slightly fragile device and I wouldn't use it for touring but for rehearsing it's great. The signal passes through many layers of concrete walls - I know this because I've gotten up to get some coffee in the pentry and the signal remain clear-ish.
The receiver is completely made of plastic and I am confident they will break eventually - especially the cover for batteries. But, again, we only use them for rehearsal so it's a fair deal.
The included earphones are total garbage and not one single part of my essence can highly recommend you to throw them away and get a better pair. They are only good for lousy ear protection - and fail even at that.
All in all, this is a great product for dipping your toes into the world of IEM and I highly recommend it. It does it job and will allow you, and your band, to successfully have working in-ear monitoring for cheap. And it will teach you what more expensive devices does better without even trying them.

I've used this In-Ear systems for around 5 months now, and it works!

Regarding the sound quality: It's not great, but it's okay enough for me. You have a slight constant noice which does not be affected by environmental parameters. I've tested it quite thoroughly:

I'm using it in a fairly wireless setup, where we have multiple monitoring devices, out of at least 2 are of the same brand, together with both wireless microphones and wireless broadcasters from our instruments.

I've also tried it with no other wireless equipment around, including WiFi routers etc, and I haven't noticed any difference in quality, the sound continues to be okay.

The transmitter is really easy to use, choose if you wanna transmit broadcast or stereo, choose a channel and you're good to go.
The receiver is light weight and also really easy. Set the appropriate channel with the buttons on front, turn it on and off with the big knob on the top. This knob also adjusts the volume.

The headphones you get with it are not super good, but since they're connected with a standard 3,5 mm jack you can use your headphones of choice.

I'd definitely recommend this for people who wants In-Eer monitoring but aren't prepared to pay the big bucks