I have a Denon 3803 and an HSU STF-2 and I am about to purchase the M60/VP150/QS8 combo to go with it. I want to connect the sub using the LFE and the receivers crossover, not the speaker level connection. The reason why is because I have a new house with speaker wire and cable run in-wall where everything will be located and I don't want to run speaker wire across the floor from the sub to the speakers. When listening to music, can I achieve the same sound using the "LFE + Main" selection on the 3803 and set the M60's to "large"? Would I change that for watching movies? and finally where should I set the crossover.

Using this setup am I sacrificing anything? Thanks.

Absolutely not losing anything. In fact, you may be improving things. You can get the same sound with the regular setting, I believe. LFE+Main would run LFE through the M60s, which is not necessarily a desirable thing. Most people set the crossover at 60 or 80 when using the M60s, and leave the speaker set to small, so the bass from the main outputs goes to the sub, not the speakers.

Althea, you should certainly use the coaxial cable connection rather than the speaker level connection. However, to take full advantage of what is actually bi-amping(though not often referred to as such)you should take the lowest bass load off the 3803 and the speakers by setting them all "small", with an 80Hz crossover. The "LFE + Main" subwoofer setting isn't advisable in my view since that would involve sending the full range to M60s set "large" and also duplicating the M60 bass in the STF-2.

Speakers "small", crossover 80Hz, STF-2 internal crossover switched out.