in many cases for metal rhythm purposes i prefer the vc over actually tuning lower on thicker strings, theres just more clarity , on the thinner gauges, especially when you go in 7 -8 string territories like using a 54 and vc 'ing it to A versus using a 64 at A by tuning. it also helps if you prefer higher tension.
i have had cases, where people fail to make out in person or even hearing on camera audio that i am using a vc to play 8 string stuff on my 6 strings that i am actually not tuned so low.
Using axe as an interface it seems there's next to no latency ,felt when using vc first in the chain i also use it with brighter amps . In many cases peq'ing your DI into axe after the shift helps bring back the sparkle you may feel is missing when shifting lower, observing rta differences, between actually tuning low ad using vc on same guitar and try to dial in a curve thats as close as the real tuned thing,
The cleans could be better but thats the case with all technology available for this purpose.
if you tend to use a tonne of lead fx while using vc, 's it may not feel as natural, but again the issue is with , every solution for this. axe 3 pitch shifter is the best all rounder there is, in this regard, as against a physical pedal with very limited possibilities.