NOTE: Not a great comparison as I am comparing it to my BC coilovers. Coilovers is a completely another level.
Initial impressions: The drop isn't terribad. It actually almost looked similar to what I had my settings on my coilovers, difference was probably 5mm higher than what I had. I am pretty positive that these are lower than the Eibach's when I had those too. Actually I am pretty positive, they are lowered by 50mm. 50mm = 1.968 inch.
Driving impressions: Awesome, actually thought I had coilovers on for a second. But, I could tell the difference when pushing the car harder. For the amount of drop, they are not that bouncy at all, better than the BC forsure. These are definitely great for daily driving as they felt comfortable and quiet.
Handling: It handles good for what they are, not great under hard turns or acceleration. Acceleration and stopping you can feel the car squat more compared to the BC coilovers. But will be hardly noticeable for daily driving. On hard turns, you won't be able to push it as hard. I felt some body roll, possibly sway bars can fix this.
Noise: I must say these are very quiet compared to my BC Racing coilovers. No more harsh noise when going over big bumps(could be just the fact that BC uses pillowball mounts, increasing noise for performance). Also helps that Tein uses whats called a silencer rubber on their springs to eliminate "coil snap".
You can find more pictures and information at: http://teinusa-blog.com/08-nissan-altim ... g-springs/
This picture was taken by Tein and from Tein's blog:

Note: My tires are running smaller than the stock diameter. I took out the junk in my trunk
