I've not got far with it yet, but my experience has been largely negative from the perspective you describe (i.e. actual functionality/experience).
1) You have to install it, which seems a tad unnecessary and severely limits what devices can interact with it. It'd be one thing if the DM had to have a PC, but everyone has to have a PC which can run it. For my group that is definitely not true - it's particularly not true for the devices they use VTTs on.
2) Logging in and installing it is not a smooth or seamless process. It is a multi-step, annoying process, which requires to actually go find your login details and manually enter them. That's going to cause some people to bounce off, just because of that annoyance.
3) There's no built-in tutorial elements that I've found. That's pretty bad for a released product, and will definitely cause even more people to bounce off the product.
4) Particularly because the UI is absolutely not intuitive or well-designed. I'm sorry, I have some experience designing UIs (not a huge amount, but not none), and decades of experience using them, and this is a bad, counter-intuitive one, where a lot of buttons don't do exactly what you'd expect, and there's no natural "flow" to the UI. Could this improve? Of course, but it surprising that they felt this was the state to release it in.
My only really positive impression was:
5) The minis are pretty nice and move in a nice way. Not astounding, but definitely solid.
I only spent less than an hour with it, but given I was ready to spend a lot longer, that's not ideal.
Overall my feeling is "you only get one chance to make a first impression", and this was not a good first impression. To be fair, several other VTTs also have mediocre or bad first impressions, but with an alleged team of 250 people working on this, and AAA videogame money behind it, I was expecting the first impression to be at least as good as "modern" VTTs (i.e. those that have emerged in the last five years). It was not.
Will I give it another go? Maybe. I think I'd want them to add an in-engine tutorial at the very least before I did.