I too think the Sonos is a great device with supporting application. I would have agreed with Simon and the 'light years' statement a year ago, but, having done a few tweaks I actually think the sound quality is surprisingly good; that said Quboz via the microRendu is simply better.
WRT mR and adverse commentary: There was a storm (in a teacup) started by one site / poster. He later admitted that his methodology was flawed, in a number of respects. This also led to criticism of the IFI PSU. IFI had some independent tests run, I believe, and posted the results online. Regardless of this I decided to buy the mR and have been very pleased with the results, even with an IFI PSU. I also have an SBOOSTER on order, as recommended by Hans Beekhuysen, and will be giving that a spin when it arrives.
Listening to Quboz via the mR has been interesting. It is hard to do proper comparisons as the recordings I have are not necessarily the same master as those on Q. My general impression is that via the mR I don't suffer any digititus (if you know what I mean), in fact I feel that the music is rolled off at the top end. Overall the SQ depends, as always, on the quality of the master. I have a playlist where I compare two versions of the same song on Q to demonstrate 'poor' against 'good'. I was listening to Roger Walters live version of The Wall last night and was simply blown away by how good it is.
WRT setting up the mR, the different modes represent different complexities. If you have no NAS and little networking experience then there is a journey involved ....but, this is a very helpful forum.
Jump in, the water is surprisingly warm. You can get a SUPERB digital front end for a great price.