Well I have owned this amp for a few weeks now and here are my observations: I'm using this for rehearsal, teaching, and practicing. I have not gigged with it yet--much prefer the tone of the Tube 800. It has a great clean sound--I really like the Little Mark amp model and the GK amp model for punchy, clean sound. I feel that it has more low end emphasis than the Little Mark 2/3, and it seems a bit "boomy" and not as bright/articulate as those other amps at high volume. My benchmark for a Class D amp is the newer voiced Little Mark Tube 800 from the last couple years. The older Italian LMT 800 had a "scooped" sound but the newer version is just amazing. The LMT 500 is also great but has less airy highs, and the low end rolls of dramatically below Low B (I have a Hipshot to drop to low A, and low G. The LMT 800, Mesa d800, Warwick LWA 1000, and even the LMK don't drop off as much as the LMT 500). I have compared all of these amps with the Mesa D-800+ (Fantastic amp but not as growly and plug and play as the Markbass Little Mark series), Markbass LMK (going back to this as a two channel head), the Warwick LWA 1000 (super powerful and clean, without much growl, but very nicely featured, two channels, and a GREAT sounding 1/8" input and headphone output). I didn't find much in the distortion/drive amp models that I liked. The distortion sounds are digital sounding to me, and it seems really hard to gain it "just right" to get that touch responsive overdrive tone. The other effects sound great--especially the envelope filter, chorus, reverb, and delay. I wish you could save an effect to an amp model on amp selectors 1-6 on input one and two. You can only select one effect per input that is applied globally to that channel. Also, the amp selection will not save your gain settings which is unfortunate. Ideally, I'd LIKE to be able to save a different amp/effect combination for EACH of the six selections on each input. Overall, the amp is really simple to use. I have a couple other comments and niggles. The gain structure is COMPLEX. The channel gain likes to be on the "hot" side it seems. Then, you have "level" gain per channel, "Mix" when mixing the two channels, and then Master. That's FOUR gain stages when mixing channels, three stages when using just one channel. I have not heard ANY distortion and the amp seems super powerful. It suggests more than 500 watts to me. The tuner works AWESOME even on the low B string. It is VERY hard to see the settings on the knobs. The software works great, but you CANNOT adjust any of the parameters of the amp models. There are three parameters per effect which you can tweak. You can also adjust the BOOST gain. The footswitch works very well also. WARNINGWARNINGWARNINGWARNINGWARNINGWARNINGWARNINGWARNINGWARNING: WARNINGWARNINGWARNINGWARNINGWARNINGWARNINGWARNINGWARNINGWARNING: The AUX input level is INDEPENDENT of the master volume! You need to turn your 1/8" input device WAY DOWN. I'm using an iPhone 7 and i usually only need 2-4 volume out of 16. When I use Siri, there is a 500 WATT BEEP at the start of dictation, and a 500 WATT BEEP at the end of dictation, REGARDLESS of your volume settings at the amp, OR the device!!! *** *** *** *** *** *** *** *** *** *** *** *** *** *** *** *** *** *** It happened today in a lesson and my ear hurt for about 10 minutes. We are talking about LIABILITY here. For me, enough is enough. It is a deal breaker. I can't have this happen EVER again so the amp is going back. I PRAY they can fix that with a firmware update. It has happened too many times. It will scare the hell out of you. I'm trying the Multiamp next. That one does not have two channels…darn it. I LOVE Markbass but there is a few flaws with this product. I do think it sounds very good overall but it is not as tweak able as I would like, and the 1/8' input implementation is a disaster, at least with an iPhone.