"Very impressive device. Most tones sound and feel great to my ears/hands and I’ve played electric guitars since the 70’s. Now professional muso since the 80’s. Not a high gain guy can’t advise about some of those amps but the clean to dirty tones hit high scores in my book. I’d prefer slightly less compression for the ’65 Twin but backing off the guitar volume and cranking Mustang volume seemed to workaround excessive squish.

Most every model is very useable and the device plays nicely with connectivity, bluetooth, charging and sound capture via USB-C. Great jamming tool and actually a useful Bluetooth mini phono headphone adapter for those of us with Lightening connector only iPhones. Also used similar manner in cars with line inputs to sound system.

Relatively minor complaints - difficult to see the orientation of +/- switches. Not too big a deal if used regularly and familiar with the configuration/orientation but some visual contrast in those +/- recesses and the power ON/OFF/BT switches would go a long way to more easily enjoy this little guy right out of the box. LED colors can be a little difficult to tell which is what but scrolling usually finds a color I can easily distinguish and go from there.

I tried other $40-$80 guitar headphone amps and they were okay but returned em once the Mustang Micro showed up. Fender Mustang Micro sounds great, bluetooth feature for jam tracks or simply routing bluetooth sound from phone to mini phono amplification such as automobile or powered speakers equipped with mini phono line inputs.

Oh, the clean studio preamp is useable for acoustic or bass guitar. Majority headphone amps don’t seem to have that option. Can’t say much about battery life yet - it’s allowed hours of playing between charging so at this point ample capacity IMO.

While the effects have limited editing they’re pretty close to what I expect from guitar effects. I kinda like like the preset speeds, levels and depths available. Very useable.

Speaking as someone with pro experience using Helix, Fractal, Kemper, Fender modeling has been improving. These are the most convincing amp IR’s from Fender I’ve experienced to date.

Would I attempt a full bore professional gig with this device? Probably not yet but for low-key casual gigs I would give it a shot using a mini phono or USB to XLR DI box.

Update - Even more impressed since latest FW update 1.9.54

Among minor tonal improvements to effects and increased volume for the Deluxe + Greenbox OD this FW also disconnects USB recording level from master volume and revised tone control to NOT affect BT audio. Other bug fixes and enhancements.

MORE UPDATE - got my spare…

Sadly people learning the hard way passive acoustic guitar pickups (UST) will not open the signal squelch circuit Mustang Micro employs to keep unwanted noise to a minimum. This is only a problem for acoustic pickups with NO onboard preamp. If your acoustic instrument requires a battery Mustang Micro will probably work for clean preamp setting. Patching after preamp (or wireless) seems to workaround the issue if you need to capture tracks into DAW or live performance. But it's no longer a simple headphone amplifier.

Could be an “opportunity” for the bright minds at Fender to offer something more specific to passive acoustic guitar UST systems? Heck yeah, some of that acoustic IR stuff they’ve developed of late. Mic IR’s, preamp and efx choices tailored towards UST passive systems in a similar Micro format/package.

UPDATE- Still my favorite quick amp solution for electric guitars.

Recently allowed my #2 unit sit unused for a month or two and happy to report battery suffered very little SOC loss. Measured resulting charge about 7mAh needed to top off. Little more than 1% capacity loss."

"My son originally purchased another brand and had to return. This item is solid and easy to use. He loves it. The sound quality is awesome! Highly recommend this product."

"This is my favorite pocket amp like this, it is just built out of plastic and kind of likes to slide around a little bit in my guitar and my bass, but I'm pretty sure that is a problem with my instruments not the product. This thing has everything from funky auto wah stuff, echoy psych reverb sounds, hard métal and punk sounds, i love this thing, and for the cherry on top you can use it as an input on your computer like an interface, and i have not had a problem doing so at all. I will say however when I bought this I was under the impression that there was some kind of phone app that connected to it, there is not, but this thing is still great otherwise, my only problem is the plastic construction and I'm not sure how much abuse it can take but as of now it seems sturdy enough."