I still say the ED100 is one of the best kept secrets. Everyone goes for the faster ED80 or larger objective 120, but put a FR of 0.8 into the train of a 100, and the images blow you away!
Below is my full size shot of Eta Cariane, cropped to just show the "core". Just look at the colous, the extreme white, the DETAIL! And that's with an unmodded Canon DSLR. And this is a SINGLE 10 minute exposure, no darks, no flats...
http://imageshack.us/f/7/closeupcore.png/