Thought I’d follow up here (~1 year later) to give my experience.

First, I was wrong about the Sonance speaker pricing...that was per speaker (single). With my 30% trade-up credit from an old Connect (was using with an aging 5.1 receiver) going to an Amp+Sonance In-Walls speaker package, I found the price to be quite reasonable and went for it. I tried to save on the sub and bought a Klipsch 12”...which my wife hated. I can confirm the system would let me TruePlay with the 3rd party sub, but ended up returning that and buying the Sonos Sub when they had a refurbished deal on Gen 2s (right before the Gen 3s came out). Much prettier looking and the wife approved. The white version blends into the corner quite nicely (thought it would look stark and stand out more than black, but it does not).

I love the in-wall setup. One thing I would HIGHLY recommend are the back-cans that Sonance makes for the in-wall speakers (found mine on BestBuy for ~$50 for the pair). Made a huge difference in projecting sound into the room (and away from the bedroom on the other side of the wall). Sonance makes big ones that install behind the dry wall for new build installations, and small ones that screw into the back of the speakers for old-work installs. The screws perfectly align with the Sonos-Sonance speakers and the cans seal well around them (Sonos should sell or include these!). I TruePlay tuned them after the back-cans were installed and it sounds amazing. I’m not a supper hi-fi type guy, but can say that TruePlay does make a noticeable difference in our living room that has wood floors and a high-pitched ceiling. Your mileage may vary.

My wish list from Sonos:

1. Make volume level for TV input independent from when playing music (i.e. have it jump back to the prior level used for that input/source). We have to crank up the volume up much higher for TV and have to quickly crank it down when regrouped it to music. Would be nice if it just remembered where it was last time the TV input was being used.
2. It’s great that the Amp can ungroup itself from other rooms when the TV is turned on...but can we get it to re-group once the TV is turned off? What ends up happening is the wife/kids turn off the TV and it never goes back to music until I get around to regrouping...so using less than I would like to (i.e. getting less value out of it). This would by my #1 request, but without the volume jumping back down to the “music level” this would actually be a nightmare if it just randomly jumped back into the music grouping at full blast.
3. Center channel support by pairing a Beam, etc. This is a distant #3, but might be nice….you can see below I’m not a huge multi-channel guy.

Final thoughts….if you’re comparing this to the Arc I would think about your room size more than having all these separate channels from Dolby Atmos. You likely have more stereo content you are listening to than even “regular old” 5.1 content, and good stereo separation likely makes a bigger impact (IMHO). I haven’t listened to an Arc, and it wasn’t available when I bought my setup, but other than weighing the install hassle (which is real) I think I would still go with the Amp. Just for kicks I wired an old Connect:Amp as rear surrounds (before the S2 upgrade) and threw up some old surround monitors and watched an action flick (yes, it allowed surround TruePlay tuning even with my old Polk Audio surround attached to the Connect:Amp)….having the surround channel wasn’t even worth the wires going everywhere. There just not enough actual content being directed there to justify it. The sub on the other hand makes a big difference, and not just for movies of bassy music. It just allows the full depth of whatever your listening to to come through. - Just my opinion!

Hope that’s helpful for someone. Feel free to ask any questions about the setup or experience.

These are things that have been requested before.  I think they appear pretty simple, but get more complicated when you explore them more deeply,  Mostly because I think there’s going to be a wider variety of what people actually want in these areas.  For example I get that you would want a separate volume for  TV and music playback, but I would want something slightly different.  I want a default initial volume every time I turn on music, and the same for TV, depending on the time of day.  I don’t want my TV linked room to join the prexisting group when the TV is turned off.  I actually want the entire existing group to turn off when the TV is turned on...depending on what’s in the existing group.

Perhaps it would be nice if Sonos built in the ability to setup your own routines based on certain triggers.  You can do a lot of stuff with 3rd party controls, but to my knowledge, you can’t trigger events based on actions that happen on your Sonos speakers.

As for the Beam as a center channel only, I won’t go there.  I would claim it’s never going to happen for various reasons, but now we have the dual sub option that I thought would never happen.

There’s some assumptions about how people watch TV here that I don’t think necessarily apply.  For me personally, I stream a lot and get a lot of surround audio.  Having the rear speakers there are worth it.  As well, my room layout makes using a soundbar a lot more reasonable than wired left and right channels.  But you’re point about considering the room playing in, and what content you have most of the time, is absolutely true.  There is no one size fits all, which is why we have options.

How is Truplay with the speakers?