RodneyVikens t. The only thing I can never get used to is pedal distortion or overdrive simulators on multi fx boards or pedals. The same way you use auto tune on voices and can clearly hear it, there is just something in an amp simulators that has that sound that irritates me.
One thing I've learnt about multifx's - generally, cab sims sucked. Not as much as auto-tune, but it's darn close. I've underestimated just how much a speaker does for guitar tone, particularly for overdrive/distortion tones. Not that a decent cab sim solves ALL issues - but it really helps the 'real feel'.
Now we can play with custom IR's, which is much, much better - though one still has to find a decent IR (not all are equal or good).
Mostly I'd want plug n play usability (which I feel the Katana has) - because I want to play not program ? But still, one has to be familiar with how guitar is gain staged, where boosting the signal has the effect you are looking for, how a 1x10, 2x12, 4x12 colour the sound and more... before you'll get the most of out any multifx (I think this also applies to pedals).
Imho, that understanding can be hard earnt...(though in hindsight, it all seems common sense and I was an idiot who read the manual but didn't understand it!)