So, I should start by saying that I'm of the opinion that a separate neck cream isn't really necessary. Those ingredients that fight aging on your face? Well, they work on your neck and chest area too. I do think that the skin in those areas is a bit different than the skin on your face (your eye area is even different than the skin on your cheek after all), but I'm not really sure that you need a completely separate product for that. But, I'm not a derm. (Picture me shrugging my shoulders here.)
So, in my lazy girl, get it done fast world, I don't use a separate neck cream. Instead I use a tad more face serum, cream, etc. I smear it down my neck, on to my chest and any extra beyond that goes on the back of my hands. (Notice those areas? They're the ones we're most likely to forget to treat and they give away your age!)
But, since I wasn't lazy while testing out the Somme Institute products, I actually used a neck cream! I applied this after the other steps, after wiping on Transport, applying serum and smearing some A-Bomb on my skin. Neckline contains the same MDT5 as all of the other Somme products, so you're getting the same vitamins deep into the surface of your skin and fighting aging while improving the appearance of your skin.
Neckline is a thicker white cream with a scent similar to A-Bomb, though lighter. It feels very creamy as it is applied and it takes a few minutes to sink in fully. It is very hydrating and if I applied a bit too much I did notice that my skin had a little bit of a sheen on it afterwards. I didn't find this bothersome since, really, are you going to be applying makeup down there? No, you aren't. So, I just let it take an extra long time to sink in.
I think after using Neckline for a month my neck skin does look a bit better. Primarily because it actually had attention paid to it consistently! It is softer and more moisturized. I don't have any aging issues on my neck (I'm only 34), so I can't really comment on those results. I'll be leaving Neckline on my countertop and applying when I remember.
Note that the presence of vitamin A in the MDT5 technology means that this entire line should be avoided in pregnancy.