Considering they all sold out and pretty immediately as far as I remember, yeah, I would say they were popular!
If they were liked afterward, that's a bit of a different story. I only heard that Miku was static, not much else, but damn sucks that it wasn't that good, I'm sorry to hear that!
I would have taken a picture with Rin in a heartbeat, but that... wasn't even an option... >.> (And it's not like it would be too difficult either!) I think Crypton is still learning, after all these years (Like how they added a Luka speech this year) so I hope they do better! Like I would have expected that you could choose Miku's pose at least? Since they have a lot of premade ones, but all the photos I saw Miku is in the same pose, makes it feel a bit less unique! ><
Additionally just looking at the official page it looks like VIPs for London and Barcelona only get in 30 minutes before? That has to be a joke, right? :/ Or at least merch sales at a different time? Aaah I don't wanna feel let down :c