This is an amazing color and I love the entire SH CSM line. You NEED to use a base coat though. This will stain your nails! That being said, if you do start with one of the Sally Hansen base coat products, this stuff will go on like a dream and be amazing. This looks particularly awesome paired with SH CSM in "snowglobe."
(I bought this polish 3 days ago and have worn it for a little over a day, so I can't comment on it's lasting ability.)
First off, I would like to say that the color of this polish is rich, dark, and gorgeous, perfect for fall. It is extremely pigmented and opaque (deep, dark navy nails in one coat, but I applied the recommended second coat). In regular room lighting and from a distance, the polish on my nails look almost black with a touch of blue. It's not until it's up close or in direct light that you can distinguish it as navy rather than black. When the bottle is held close to a direct light source, looks almost like a plum navy with metallic plum flecks.
Also, I read that it's a close dupe for Dior's Poison Blue if anyone's interested: (http://thenailphile.blogspot.com/2008/08/so-you-missed-diors-poison-blue-bleu.html)
The Complete Salon Manicure line claims to have top & base coat in the formula. Unfortunately, in my color-infatuated and excited state, I made the mistake of testing the polish on a nail without using a base coat. This left me with a light, blue-gray stained nail. Learn from my idiotic mistake, girls! Definitely use a base coat with this dark of a color, regardless of it's "base coat" claim!
The rubber ring around the top/applicator helps with grip and control. However, I found the wide, flat, brush awkward and deposits too much polish in one swipe (running one side of the brush against the opening to remove all of the polish from one side helps to prevent "polish over flow.")
In the bottle, this polish looks like a very dark blue with purple shimmers. On my nail, it was a so dark it's almost black blue. I liked the color a lot because depending on the light it would shade from blue to black. The actual formula of this polish is nice and the brush is obviously expensive and took a lot of engineering to make. I appreciate the quality of the brush, and I think if it works for you - huzzah. But I really struggled with how wide the brush was and how much product it picked up so ultimately I'm not going to keep this polish. It's too bad because I loved the color and formula.