I just got the Early Access to work (heh), and I have... thoughts.
One, the UI. It's fine, I guess, but nothing special. I do like the chosen color pallate though. However, it was a bit difficult to navigate at times, but nothing I couldn't do on my own.
Two, installing singers. Worked well enough, but it wouldn't let me target my OpenUTAU singers folder, which was a little annoying, but I just installed two banks through their method and everything worked well.
Three, actual synthesis. Good lord, the synthesis. It is... not the best, to put it mildly. I used the voicebank Vlad V Act 2, an obscure one, but I like him. Anyways, he has pitches recorded at C3, G3, and I think E3. I laid down a simple Do scale, and uh. It was bad. Almost the whole time it was playing, it sounded like either it added a LOT of vocal fry or just ungodly amounts of engine noise. On further tests, it turned out to actually be engine noise. Again, C3-C4 is the exact range this bank was made for, and it sounded genuinely terrible. Higher notes sounded better, but not by much. I'd share samples, but I don;t know if I'm allowed to here.
Four, errors. SO. MANY. ERRORS. I can't import any files, or error. I can't switch active voicebanks, error. Sometimes if I try to put down notes, error. I can't render some notes, error. There are just so many, good lord. And not being able to import files most of the time sucks. There's more I forgot about here.
Five, imports. When they DO work, they don't, really. No note lyrics render correctly at ALL, they're either vowels or just A.
I literally can't use it like this.