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As far as my $.02, I would also go 5.0 first. Although your 150's in the front are too small to adequately reproduce LFE, but since you are in an apartment, you probably can't go too crazy with LFE. You might want to get some good headphones (Sennheiser around ear) for late night watching. I used to live an apartment, and the Sennheiser saved my sanity, until I was able to build my own theater.