7 digital just added MQA files for download to their
test bench.
Even though we don't yet have MQA decoding, I would encourage everyone to take a look at the test bench referred to above and compare the various formats. All downloads are free and there are plenty of MQA examples.
On the Kate Rusby album the comparison between standard FLAC and un-decoded MQA is quite obvious - it's most easily heard by listening to the tail end of her vocals before she draws breath for the next line. Almost all of the "lispiness" has disappeared, making the music sound much crisper.
I'd be interested to hear views on un-decoded MQA versus high res FLAC on the same tracks from the test bench - my guess is that the un-decoded MQA will get very close to plain vanilla high res PCM.