My AX8 amp sim is better than any amp of its $$ value. But cab sims suck. Every one of them, by design. They suck for they are one single eq filter applied to every different note and chord. Since modern cab sims provide an average cab reaction to a sine sweep, a pink noise, and such, only complex wide-range chords come close to sound realistic whereas high pitched single notes sound the fakest. A realistic cab sim needs a different EQ for every different note and interval.