I wanted to glowing red eyes... so I kept the seal. I looked pretty cool, plus the dyes and clothes made it impossible to see that I was old. The weird thing is when I went back to Reaver my eyes turned back to normal O.o But it's cool, there are ways to get rid of the negative effects of that quest.
I did the same as the guy above me. So while I stood there, refusing to give up the seal, believing i would retain my youth, laughing manically, the joke was on me. Oh well, it didnt really change anything, I dyed my hair from grey to brown, then when i took the brown away to change the color, my hair reverted back to being blonde (Im 100% good and 100% pure) and when I got a new tattoo all of my "oldness" went away.