The 99 Insignia and for that matter, all of the Insignia’s in the 90’s are built to drink upon release and improve with bottle age. I'll refer you to this site on the Phelps website.http://www.jpvwines.com/general_news_spring2002.html
The 99 California Vintage in general will benefit from 5-10 years of bottle age and many of the top producers will benefit from 10-20 years in the bottle with proper storage. The 99 Insignia seems to me to be about a 10-year wine. The best part about Insignia is that you can drink them now and drink some over the years to determine how the wine has evolved.
My experience with Insignia is that they can go into a shutdown phase, the 94 did and has come around beautifully and drinking almost as good as its going to get. The 95 did and I found it to be a rather long time, 2 years. It is just now coming around. These wines still need at least two hours of decanting before drinking, I prefer 4 hours.
Depending on the number of bottles you have, I’d drink the wine at least one bottle per year to see where it is. You’ll probably never be disappointed.
Not only are these GREAT wines but because you can almost always find some makes it clearly one of the top three wines produced in California every year.