Oh, this seems fun
V1: Meiko is def the favourite<3 I’m not a fan of her v3 or nt, but her v1 vb is really giving. Least favourite is probably Leon. I tbh just don’t like male vbs in most cases hehe
V2: Going to crypton, my favourite is Len Act1. I like both Lens but Act1 sounds a little more fun. The least favourite has to be Lily for me. She kinda sounds like an xsy of Gakupo and Pico.
V3: it’s ofc Tianyi, no explanation is needed. My least favourite is Lily native, but since it’s basically the same vb as Lily from V2, and Lily
V3 isn’t too different either, I’d say that my least favourite V3 is…. Yohioloid? Not really that I hate him, but he sounds like he always has his clearness in max.
V4: My favourite vb here is once again, Tianyi V4 Meng, but since it’s a port of her og V3 I’ll choose Unity-Chan. She’s very fun to use, and is super expressive. My least favourite v4 will have to be…. Cyber Songman? Once again, I don’t dislike him, but he seems rather boring to me.
V5: Tianyi V5 Meng hehehe… but since she’s also a port of her V3, I’ll choose Tianyi Wan. This vb is a newly recorded append that is like Tianyi, but more relaxed and soft. The least favourite will have to be Chris. He just sounds weird to me.
V6 (so far): My favourite will have to be Fuiro. She has so much charm in her. And the least favourite is Sarah or Allen. Still haven’t decided which one of them I like less.
VX-B (so far): Ik that rn we only heard demos, but my favourite is Kazehiki. I always liked Kazehiki, and I remember how sad I was when I found out that his utau vbs were temporarily discontinued. And my least favourite vb for now is Gazen. He sounds like he had normal and shouting singing data fed to him, so he mostly sings in a normal tone but sometimes has those unnecessary growls? It’s just super weird.
And now to a few other mainstream singing engines!
CCS:My favourite there will have to be either Kasumi or Minato, I still haven’t decided. And my least favourite CCS vb is probably Yuudai. He sounds super muffled, like he doesn’t have enough data.
CAI (so far): RIME. I love her sooooo much

. And least favourite is Rose. I don’t like how she sounds at all.
VS (so far): Facourite voisona is Chis-A! I a lot of the times forget about her, but she sounds super pretty. And least favourite is AiSuu? I don’t dislike AiSuu, but she also seems rather boring in comparison to other vbs on the engine.
ACE (so far): I’ll group all of it’s iterations into 1. I think u guessed that my favourite bc there is again Tianyi. I just can’t escape her. And least favourite….. will have to be one of the 3 vbs from the Rock collection. Once again, just not a fan of male vbs.
SV (so far): I’ll group r1 and r2 into 1. My favourite is for sure Haiyi. She sounds so cheerful ! Least favourite has to be Kevin. He’s actually probably my least favourite vb in all of synthesis lol.
sorry for any grammatical mistakes that are here hehe