ive hear some pretty nice stuff with the [FONT=Helvetica, Arial, sans-serif][FONT=times new roman,times,serif]Symphony Orchestra Emerald - Kontakt 2 from Kirk Hunter
I think EastWest's Symphonic Orchestra and Miroslav Philharmonic are your best options. I like the EastWest Symphonic Orchestra the best. (As did Future Music on the Orchastral library review they did a couple months back).