Hi Deadfingers, I will tell you my experience with a chen-nian -- aged for x number of years, Tieguanyin.
My mother has given me some aged Tieguanyin which my sister has brought back from trip to China-HK-Taiwan. This is for my mom -vs- my package is the regular high mountain grade Oolong.
To make the long story short, I was so excited about trying it and go right to it the minute I've got home. The feeling I get from the aroma out of first brew is, "Emmm, smell familiar, where have I smell this before?" Then I have gone on and taste it, suddenly I realized where I have tasted this. The answer is many a restaurants.
This, of course, has caused me to examine things a bit.
First the tea leaves, shape like highest quality but color is dark as Pu-erh and it doesn't open all the way. Next, I examine the packaging, the leaves are packaged into a standard plastic-y foil type of sleeved bag. On one of the sides it says vacuum pack but it is not. Instead, it is nicely folded and then taped closed. I was skeptical when my mom handed it to me but just think to myself, "may be because special tea requires the special (unconventional) package because of the lower volume of production.
So, if you asked me, I'll say it taste like expired or lowest quality "black"er tea. Like ones you can get for about five bucks at a grocery store, for a pound in a, sometimes, nice canister.
It's aged good Oolong (once, befor it aged) to sell, expired good Oolong to taste, for me anyway.
Why not buy the least amount and let me know what you think?
Hope this help!