New speaker with imaging

For orchestral music try a line source or an electrostatic type speaker. Ones that come to mind are Martin Logan, Quad and Wisdom Audio. Depending on your price range.

If you like the B&W sound you have now, by all means, stick with that line. As suggested above, the 803D would be a substantially improvement over what you have now. And at 8K with a discount, you'll be doing alot better than your budget of 10K. And you'll have a speaker that you will hopefully enjoy for quite some time, and also have great resale if you decide to sell.

Here is an Audiogon discussion link where there are many good recommendations on speakers that image.

http://forum.audiogon.com/cgi-bin/fr.pl?cspkr&1053643146&read&keyw&zzlegend

IMHO, Squidboyw has offered the best advice so far. Given that you have NOT told us anything about what you have done to improve the sound thru you M804 speakers, we have to assume that you did nothing! Might be a very bad assumption but you gave us no choice so far!! :-) Please tell us about your room & its acoustics & what you have done to ellicit the best from the M804. Again, IMHO & being a former B&W owner, if B&W made a series of speakers worth owing then it was the Matrix series. It's that M801 sitting in George Lucas' studio that's B&W claim to fame. The Nautilus series speakers, in comparison, failed. IMHO! If were you, I optimize the setting before letting go of this gem. Or, finding a M801 as a replacement if you cannot optimize the M804. \
Most people buy & use audio gear as it is manuf in the factory rather than buying a good pedigree piece of gear & then modifying it for improved performance. Often, I have found that the performance of a good pedigree piece of gear, when modified or optimized in its setting, far exceeds the purchase of a new piece of "latest & greatest" gear.
Anyway, FWIW. IMHO.

Ok guys I'll try to answer everyone. No I haven't heard the new 800 series. I don't know if it was the amp combo (tube) but vandersteens always sounded plummy/ripe to me. Would my solid state amp help that? I also don't know if I am ready for an electrostatic speaker, I like Mahler and organ music too much.

As to the room I am lucky to have a dedicated basement. The Room is 25 ft long and 14 ft wide. However the rear of my space has bifold closet doors so not a good place to put the system. Also I don't like nearfield listening so I am inclined to forget about putting them on the long wall. Lastly there is a flight of steps into the basement, takes about 2 feet away from the 14 ft width. I am forced to use the speakers on the long wall with the right one somewhat close to the steps. I have placed a child's mat on the stair wall to minimize reflections off the paneling. Hope this helps for suggestions. Incidentally the amp preamp combo is an AI3 with a Sonogy Black Knight providing 175 watts and current. The speakers of course are biwired.