Tonelab is a good investment, especially for practising it's amazing, really.
I would change the EH tube to a JJ a grade (around 10 GBP) as it's a little darker and smoother, the EH is quite a bit scratchy. And then it will take some time to tweak, I used to use too much presence for a long time, now I realise that with lower presence settings it's much closer to a real amp (gotta A/B it from time to time).
One thing: there are no operating system updates, amp upgrades or something. Korg/Vox don't offer it and I have the feeling the OS is fixed and couldn't even be upgraded without replacing chips. So what you get is what you get.
On the other hand that is positive as you spend less time dealing with gear software versions management and more time with playing:)