Now, my leap into EU isn't even close to being over. I've only read portions of Shadows of the Empire, and the parts I did read, I found good. Later on I'll try to buy it in paperback instead of reading the ebook to get a better perspective for my own personal opinion, and then move onto the Thrawn Trilogy.
Until then, I'm interested in everyone's opinions of these two central EU villains and their tales.
So far I see a trend of Thrawn Trilogy being almost universally accepted as great, while Shadows seems to be more of a mixed back.