Best HT Speaker "package" for under $2500??

get a used processor here and a multi channel amp, and spend the rest on good new matching line of speakers. Others may differ but I think used for youe source is a great idea...buying all the same manufactures speakers will give you the best image of sound possible.
If you already have a good 2 channel rig in a dedicated room maybe look into Definitive Technology for theater speakers...good price and performance for movie sound.

Check these out. I have a friend who owns these and they are an amazing bang for the buck:

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http://www.av123.com/products_category_pack.php?section=speakers&brand=3

http://www.audiorevolution.com/equip/rocket_speakers/index.html

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If you're looking new, according to June edition of The Perfect Vision, you should be looking at Energy act6, Paradigm Atom, B&M VM, Epos ESL3, Mirage Omnistat, Totel Dreamcatcher, Infinity Primus 360, Magnepan MGMC1, Focal Chorus, PSB T55.
If you're looking here used, you ould go up a notch ot two, but it may be tough to find someone schleping a fully matched sytem.
I suggest you get a copy of the Mag, and see if you can back into one of their more expensive suggestions used.