I had the old Luna Cress (basically, the same as the luna mix). When it came to putting my newborn baby in, I was very confused, because the straps where miles too big on my baby, even on their smallest settings.
I looked through the manual to that came with it, to see if I was doing something wrong, only to be shocked to see warnings that it was made for 6+ months! The pram was sold to me as suitable from birth, and I googled and lots of people online had been using it from birth.
I took it back to the shop to get a refund, and the shop assistant told me apparently, it's not suitable from birth unless you use the car seat with it, which isn't what they told me when I bought it at all! She went to get her manager so he could issue a refund, and he came back and had the cheek to tell me that the warnings in the manual were a misprint, and that a newborn baby
shouldn't be wearing straps!
I was so shocked, and angry that they could be telling new parents something as clearly dangerous as that. I fought for a refund and eventually got it (because there was noway I was putting my baby in that pram, especially if she really was meant to go sans straps).
The Luna Mix is pretty much exactly the same as the old one, and in my opinion, even if the straps had fit my baby, it didn't look very comfortable. I'm sure it's great for an older baby though, and looking at your sig I see yours is.
I found it easy to put up and and down, and it was very compact when folded. It was great to look at, and pushing it was a dream! The only prob was that the fabric touched the ground when you folded it which made it dirty, but I'm not sure if this is still a problem with the newer luna mix.
I won't ever be buying something like that from Mamas and Papas again though. Be warned that their customer service is utter shit.