The Arc alone already is a 5.0.2 soundbar that includes dedicated drivers for the front left and front right channels producing a wide sound stage.

I know this already. What I am saying is that it doesn't come close to what having front bookshelf speakers sound like in comparison to the ARC.

I have listened to the difference in a showroom: Arc + Sub + One SLs vs. AVR + Bowers & Wilkins fronts and rears + center + sub. 

Adding 2x Fives would mean that the price for the whole setup is exactly the same as the AVR system I tried but I would definitely go with Sonos just because is way simpler to use.

I think this setup would defeat the purpose of using a soundbar. It would make more sense if Sonos sold a dedicated center channel speaker.

I believe that would mean expanding the product line-up altogether which to me seems way more difficult. 

But working with what they already have and just letting the programmers do their thing, that would mean improving their recipe.

Was that in a room where the Arc’s side firing speakers had walls to bounce back off?

I am not saying this will be as good in all circumstances as dedicated front L&R, but you may not have heard the full potential of the Arc.  The effective sound stage in my media room is very good.

Your request is a perfectly reasonable one to make, but if it were both easy to do and would lead to worthwhile extra sales, I think Sonos would have done it already.

I am happy with the Arc for TV use, it’s music playback where a pair of 5s just sounds significantly better than the Arc.  I don’t care for the idea of spending $800 on a soundbar and then not using many of the speakers  though.  I would rather see Sonos come out with a center channel speaker that will act as the hub for your home theatre.  

I just don’t see that happening though as it’s likely a rather small market, considering those who don’t want a soundbar would likely opted for a wired home theatre setup.  Hope I’m wrong about that though.

Would absolutely love the ability to repurpose myBeam as a center channel and then add Ones or Fives as Front R/L.

That would mean no atmos and no DD+ or TrueHD.

For many that wouldn’t matter.  If Sonos wants to compete for the high end home theater buyer, then they can add those features to a later offering (Beam 2?), but most people after Sonos home theater have already de-prioritized those options, IMO.

A complete Beam+2 Fives+ Sub + 2 One SLs is going to run around $2460...but no atmos , DD+, TrueHD?  I have a hard time seeing that appeal to high end home theater buyers.  And I don’t think you can say Sonos customers have de-prioritized them since the must current home theater has these capabilities...and appears to be selling pretty well still.

I get what you’re saying though.  Some people may be willing to compromise in order to get that stereo separation.   And I think that would work great for those who want music streaming more than TV audio, or don’t have a room that can take advantage of atmos.  I would be fine with it in a secondary room,  but not my main room.