Bose speakers generally suck. Honest. For the money, you can buy MUCH better speakers from Paradigm, NHT, Energy, PSB, B&W, etc. Bose’s popularity is almost entirely due to their fantastic marketing and little else.
Satellite/subwoofer setups are popular because they take up so little space. And the best ones are extremely good. But the best ‘satellites’ are almost as big as the older traditional speakers you may be familiar with.
Another reason sat/sub setups are popular is because most people use their speakers these days for surround-sound video and background music. And for movie watching, a subwoofer is big improvement, because we’re not looking for pure fidelity as much as a jaw-dropping experience, and that means your speakers need the ability to give you that chest-pounding bass when explosions go off and stuff. And subwoofers excel at that.
Anyway, the main problem with sat/sub combinations is that they often lack midrange. The bass is great, the highs are great, but the middle stuff can be pretty muddy, because neither your 12"-15" subwoofer driver or your tiny tweeters are very good at reproducing those frequencies.
Again, in a 5.1 setup, you generally have a center-channel speaker that produces pretty good midrange for voice, and that’s all you really need. But if you like music, you’ll find many of these setups to be lacking.
The system I’m currently putting together is a best-of-both-worlds approach. Paradigm Reference 60’s for the mains, their large center channel speaker for the middle, dipole surrounds, and my current David 300 subwoofer will round it out. When listing to stereo music, everything gets turned off except the subwoofer and the Reference 60’s, which are phenomenal music performers.
That whole system will be around $3000. Connected to a Denon 3801 Receiver ($1200 or so), the combination will give you as good a sound as any system under 10K.