For an LS... hands down black.
Maybe for you.
I prefer pearl white or the look at me red.
For an LS... hands down black.
Seems high for a base '06....... Maybe worth ~$10k tops, IMHO....
my opinion:
Silver looks pretty sharp. As you stated it contrasts well. The biggest advantage though is basically that it is the lowest maintenance of all the colors. Take really deep scratches to be noticeable and water spots/dust dont show until there's a really thick coat.
Black on the other hand is the best looking. Nothing is more striking than a clean black car. It's also on the opposite end of the maintenance spectrum requiring by far the most thorough cleaning regimen. Swirl marks show up easily and plentifully and water spots as well as dust are instantly noticeable. Also if you do a rush job with cleaning it wax residue or other oily substances make themselves very apparent.
Your decision in the end. Black if you're willing to dedicate to keep it clean, silver if you want a happy medium of attractiveness and maintenance time invested.
If you go for silver, then grab a Silver Birch(JP). It gives the LS a "serious business" look throughout the night(check out my profile pic to get an idea of what I'm talking about). On a cloudy day, it will look badass. On a normal day, it will have some blue tones and at dusk, will have a purple hue. Still this is a tough choice because a clean black car looks amazing during the day, but at night, they're nothing special. I'm also debating the color of my next LS, and it's definitely between black, silver birch(again), or pearl white.