THR10X owner here, no experience with the Vox at all.
Having owned the THR10X for a while, I'm very happy with it, perfectly fine for practicing. Bandmate of mine even brought his one to a rehearsal, running it through the PA and even that worked very well!
However, I have to admit that I use it pretty much exclusively for one single sound (Brown II). Not that there aren't any usable tones on those models, you can go through the presets in the software and see how creative you can get, it's just that I prefer the Brown II by a mile without much tweaking and there is nothing in its sound that puts me off, like flabby bass or boxy mids on some other amp models or fizzy-/graininess I know from different digital modelling amps. Especially on my preferred settings, it can do some nice tight chugs. Don't expect Dual-Rectifier-full-stack-levels of chugging, especially not when playing quiet, but pretty good for the size and money.
Talking about the software: Tweaking is pretty easy and you have access to factors you can't set over the amp's knobs like cabinet simulation, effect parameters, compression, etc. Once you're happy with a setting, you can save it in the software and also in on of the amp's 5 preset banks. Just went through some presets myself and I was really surprised how much you can tweak around and the variety of sounds you can get. Still, the main theme of this amp is high gain.
Overall, it sounds good for high gain applications and then some, but if you already own a modelling amp you're happy with, I don't see a reason to get this one.