Well I don't think Muteki had a minimal standard for the beauty of the celeb, just any kind of celeb will do. OTOH, Prestige brand image is beautiful vanilla ladies (i.e. not super busty, not slim, not chubby, not loli, not MILF, not GAL) doing vanilla sex. So she seems much more typical for Muteki than Prestige.
By a strange rule of conservation of mediocrity, it's typical that a vid or an idol who's good at one aspect would be un-amazing or even lacking in other aspects. So... (most famously) one with amazing tits would be lacking in libido and/or pretended libido. Another who's good with almost every aspects, would look more mature than her real age.
So with "celeb" being a merit, it's almost required to have some demerits in some other aspects, e.g. asymmetric tits, or really really poor inexperienced sexual performance.
For us in the non-Japanese speaking world, mostly these celeb don't mean much to us. When a celeb-to-porn gossip pops up, almost 100% we have to research who she is. We can't judge say, wow A is still a top 5 TV star for last 2 years, or B was that hostess/mistress for some local politician a few years ago , or C doesn't ring a bell right away, but says she's been a full member of a pop group that I heard of before, or D was WHO??? oh she was in some sports and almost made national team and never went to Olympics or anything, or E was WHO AGAIN? she put on an animal costume for a TV commercial ages ago. If we don't have that celeb awareness that Japan locals have then celeb-porn means what? Pretty empty gimmick.
Mostly I follow celeb-porn just for the porn, so a forgettable AKB member (Yua) vs a once-hot gravue star (Shoko) vs. a shrimp in a 15 seconds TV commercial (not kidding there was such a "celeb"-porn!) all don't make a difference to me. I only fap to the nudity/sex on screen. So thanks to the conservation of mediocrity celeb-porn aren't that good, on average. So far we had two exceptions (recently) : both Yua and Shoko are huge success. Yes everyone has his judgement of them. But DMM sales ranking is a as subjective as it gets. You may not like her but she's a (commercial) success.
there are misfits in porn world
