When YSL Fall arrived instores during the Nordstrom Anniversary Sale, I fell in love with the Rouge Volupté Perle in Beige Caress #101. I had swatched the other shades and initially thought 103 and 104 resembled MAC Lame/Sequin, but on another occasion swatched them again and looked at the colors in natural light and was surprised how wearable #104 Stellar Pink was and ran right back in to get it.
I would describe it as a soft mauve pink rose with a slight (very slight) blue iridescent quality. I normally can't wear any lip items with a blueish sheen but this one is just beautiful. These have a super soft texture and feel like a lip balm on the lips but show up quite well. I like that these have a glossy sheen for the finish and they taste like candy. The scent isn't too noticeable but does smell like other Rouge Voluptés.
You can read my review of these on Beige Caress, but to recap - the Perles have a more forgiving finish than the regular Rouge Voluptés which due to their opaqueness can look a bit fake and thick if not applied carefully. The Perle formula is more natural but still shows up pretty well on the lips.
If you already have MAC Lame and don't mind the frosty quality, then I'd say it's pretty similar in color. I find adding a bit of clear gloss or lip balm to MAC frost finish lipsticks can tone down the frost quality. (Lame is one of the few shades I have gone through a full tube of, although I always find I need to tweak it a bit with gloss to keep it from looking too metallic on the lips.) Here is the YSL compared to MAC Lame and Chanel Legende (mini size):
Pricey at $34 but I like that this lipstick does not require any additional work (liner or gloss) to make it work on me. It's an easy swipe and go type of shade. I found mine at Nordstrom. I'm not all that familiar with YSL so I can't say whether or not this is limited edition or not.