Hi there, built a Chupa from Nik and it is awesome. It is essentially a hot rodded JCM 800 50 watt amp. I added many mods and I love it. Purple snakeskin as it's inspired by your 80's MTV hair metal god videos and the like. Most mods can be seen in the pics and listed below: 5 way voice switch at rear. allows for huge array of tones bright to dark and matches your gear. Mid slope switch 3 position under mids knob. Stock, scoop and boost. Thump mod 2 position switch under resonance knob. Adds more open, less compressed and bass. Gain mod 3 position switch off/symmetrical/asymmetrical clipping. Can be stacked on era mods. This gives 5 distinct distortion/gain options in total along with a few stacked variations. Circuit wise the mods were changes for bright switch values, a few resistors, feedback loop etc and fairly minor tweaks. The circuit sounds killer stock. The Presence knob is also modded and now gives at least 50% usable sweep and range vs stock which only seemed to sound good at 9/10 position. No real adjustment. The vast majority of the mods are just to add more options and variety. The stock amp sounds very good and has a lot of tones. You can even get a good clean tone by dialing back the gain. I highly recommend Ceriatone and Nik was very responsive to emails and communication. Took about a week for the chassis and parts to arrive to Canada. I did buy my transformers from Classic Tone. JJ tubes. Built the cab and finished it from scratch. Hope this helps anyone thinking about a Chupa.