the t.mix MicroMix 1 USB

I use it for a vocal effects chain because I needed a really compact mixer with an RCA output.
If you're doing small gigs with a mic and one isntrument, this unit is awesome. You don't really need more than the basic 2-band eq for small clubs with minimal p.a., and can pass your whole setup through a looper with this unit. Panning is something you don't regularly see on a mixer this small so that's a neat extra as well.
The sound quality is perfectly fine, clear without any audible noise in live settings.

The 2 biggest pros:
-It's ridiculously compact for the features. Make sure to have proper padding around the unit so nothing breaks, the knobs are mostly plastic. But on the other hand, it fits in anything really.
-USB power supply- no "oops where did I put the adapter". Use whatever cable and power source you want, just watch out for the A and V specs, but it shouldn't be a problem with most adapters.

Can't really go wrong buying this unit- I'd recommend it for most studios and small venues as a cheap emergancy backup unit or an insert/adapter unit for certain signal chains as well, it barely takes up any space and costs next to nothing.

A solid 5/5 in it's price range.

I ordered both the MicroMix 1 and MicroMix 2 as replacements for the legendary Behringer Xenyx 302 USB which I used to love mostly for its size and routing options, but has been discontinued.

This is obviously targeted at the same audience and I suspect there was a certain amount of plagiarism when it comes to design and possibly routing schematics. But yeah, that's cool with me.

One major selling point for the 302USB was the fact you could plug a average consumer-grade headset (like your standard gaming gear) into it and use the 3,5mm microphone in.

This is however not possible on either the MicroMix 1 or 2 as the circuit board does not feed phantom power to this port (well, on the MicroMix 1 it does but only for a few seconds after pressing "phantom"). This makes the 3,5mm mic jack only usable with active or pre-amplified microphones, and it kind of defeats the point of having this unit to be honest. I thought this was a fault on my units but Thomann customer service confirmed this was working as intended.

I should add that the preamps are very noisy, but that was to be expected considering the price. Maybe a FetHead can help you regarding this point, but if you're looking for a quality signal you're probably better off looking at other more expensive (but still small) interfaces.

Unit build is metal, solid, knobs are well tightened. The kind of gear you can just stash in the bag with no protection and expect to work for a couple of years.

I have used this USB mixer to input sound from external sources into on-line meetings (Zoom / Skype / WebEx) - works as expected and with great results.
I have added it to my Mac and switched to the mixer as sound input, and it sends everything in to my on-line calls perfectly :-)
Remember to add a microphone to the set-up, so that you can mix your voice with whatever else you play (instruments or music from a phone or tablet), since you can't use both the built-in mic in the PC and the Mixer as sound inputs at the same time (at least I haven't figured out how).
Some buttons (like the EQ) are a bit small and "flimsy" but work well anyway - it's great just to have EQ at this price range...
I really like that you can use both mini jack (for headset / mic) as well as regular jack (for my Epiphone guitar) and XLR (for my Shure SM58 microphone)!
Very flexible solution - great fun!!