I use this in Paris, 4.01. The new packaging includes a shine enhancing serum to put in with the colour. The conditioner included is okay.
I like this colour / brand. It covers grey and is cool-toned, doesn't go red with fading. I have about 20-30 grey, no need to dye in all honesty, but I do any way, maybe once every 3 months. I don't freshen the colour (root touch ups) because of laziness, opting instead to do a full head of hair (using 3 packets of dye - long hair) less frequently.
My normal hair colour is black. On me, Paris is a very dark, cool-toned dark-brown, almost black -- regular black dyes tend to be too opaque/severe, and a lightened brown would look weird on me (MAC C4 / Bobbi Brown Warm Natural -- maybe 1/4 - 1/3 shade darker in summer, neutral undertones). Can't complain about dryness because this comes with 'permanent dye' territory. The smell is atrocious if you're not used to it. Any initial dryness is rectified by good conditioning treatments the first week after colouring, after which it isn't an issue.
I apply dye to wet hair, leave for 1 hour, shampoo 2x and condition for 30 minutes, my daily leave in is Morrocanoil serum. I conditioner wash for the next 2 days and go back to shampooing as normal.
This is the nicest shade I've used, but cannot give a good indication of what colour would result if you were covering a lot of grey. It certainly doesn't fade unattractively on me: either that or my standards are low. Years ago I used Nice and Easy and that quickly faded into very orange-y / warm undertones and bleached my original hair colour shockingly light at the roots, but it was darker and more 'solid' in the length due to texture/ thickness/lack of light penetration. Where my hair parted, it looked like a bald spot, and the colour changed unevenly and rather weirdly. Not great.
Paris 4.01 doesn't do any of this or take me out of my colour comfort zone, I love my natural hair colour and will approximate it for as long as possible.
Adding: Saw the MUA picture of the young lady who used Paris: my hair-colour photographs much darker, probably because my original colour is black and there are few grey. Her colour is really very pretty and closer to the packet colour, although my hair brings out fewer red tones -- so I guess there's a difference depending on original hair shade and how much grey is covered.
I used another Recital Preference shade [Havana] on my hair a few moths ago and found that the resulting shade was nothing like the model's on the box and when it came time to touch up the roots, the colour was very uneven. However I did like the Recital Preference formula, so I picked a darker shade, took a deep breath and redyed my hair...
Success! This shade does seem to be almost black at first, but slightly lightens to almost exactly the same dark, cool brown shade as that on the box's model after a week or so. From there on out, any colour fade is minimal, I can go over two months between top ups, as the formula is so fade resistant. And my roots [ash blonde/brown] dye the same shade as the rest of my hair. L'Oreal - you have redeemed yourselves.
I started to go grey in my teens and this has perfectly blended them away, which is a first; I've found that dyes typically colour the grey hairs slightly lighter. Overall; I'm very impressed with the new formula.