Since this post is in the ht forum lets not talk about 2 channel.
i was asking the same question as the OP... not too long ago. it seems to all come down to this... A full frequency range is what you are looking for and for home theater you want a sub even if you have great front speakers. you will have to buy on the upper end of the sub market if you want to use monitors for the fronts. these subs are quicker in reacting at the UPPER frequencies. you may even want to get two of them. they are adjustable in the frequency range... and so is a good receiver, or whatever you are using to drive them.... so you can play with the frequencies on both speakers and subs, maybe you want them to overlap in the crossover area maybe not. it is more about the clarity than the BOOM. but you want both. so.... the floor speakers will give you clarity to a certain mid area then the sub can take over for the lower.
i was asking the same question as the OP... not too long ago. it seems to all come down to this... A full frequency range is what you are looking for and for home theater you want a sub even if you have great front speakers. you will have to buy on the upper end of the sub market if you want to use monitors for the fronts. these subs are quicker in reacting at the UPPER frequencies. you may even want to get two of them. they are adjustable in the frequency range... and so is a good receiver, or whatever you are using to drive them.... so you can play with the frequencies on both speakers and subs, maybe you want them to overlap in the crossover area maybe not. it is more about the clarity than the BOOM. but you want both. so.... the floor speakers will give you clarity to a certain mid area then the sub can take over for the lower.