The Grand Prix line comes in a jacket and a vest, both are available in a silver, red and blue. They pretty much share all the same features save for the vest being conspicuous lacking in the sleeve department.
The Grand Prix gear is made from Atlantis' Rampage fabric which like most soft shell fabrics is a DWR coated polyester fabric with a bonded microfleece inside. The seams are not taped which means while the jacket will keep you dry in most conditions I wouldn't consider it waterproof.
It has a medium height collar with a built in elastic drawcord that you can pull tight to keep wind from getting in the neck. They've put the adjustment tab outside the collar at the back of the neck which is a nice touch. An elastic double cuff at the wrist of the jacket also helps to keep out the cold.
How does it stack up? The Atlantis Grand Prix is comparable in weight to the Gill softshell or the Henri Lloyd Transition. It should be a bit warmer than the Henri Lloyd Vapour jacket I reviewed last week but that has 4-way stretch while the Atlantis is only 2-way and the reduced stretch is noticeable. The Vapour also fit me a little better in that it had slightly longer sleeves in the size medium I wore than the Atlantis does. At 6ft 145 that's not an uncommon problem for me and I think for the average size person it wouldn't be an issue.
I like the Atlantis softshell. It definitely keeps out the wind and the microfleece inside is super soft. Overall I think it's a nice jacket but it doesn't really set itself apart. If you like how it looks I'd certainly get one. It's the only microfleece softshell that comes in a vest - which I think are great for layering pieces beneath a true hardshell jacket.