Yeah, "ん" tends to be pronounced in an "un" kind of sound when stressed, so when they sang the "ん", the "u" in the "un" stood out a lot more.
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Mikaeri Bijin sounds so amazing from that preview, and the PV for it looks really promising! Already looped and sang along to that one part countless times

Tiki Bun, I already like the song, and I've had their radio rip on constant repeat and I really like the dancing that's been shown so far. I am so amazed by the accuracy and synchronicity the girls have when dancing, especially in those moves that have them separated into two lines and they're not facing each other but when they move they all move together and I think it's just outstanding. I can't wait to see more of the PV and the dancing! The girl's solo shots looks amazing as well.
Shabadabado fits Sayu so well, and is definitely a good song. Now, is it something I'd have on repeat like the other two? At the moment, no, but I am currently under the impression that it'll hit me more once we get PV/full song out. Definitely jazzy though =)