What tuner would sound better

It will depend on the ears of the listener, all other things being equal.

I am amazed how good my little MusicStreamer II sounds compared to my vintage Sansui 919 tuner

the Sansui is fuller and more nuanced with better imaging too but it does not hurt my ears to go back to the MusicStreamer

I know this is not a glowing review for the MusicStreamer but it has nice tone and can be enjoyable.

And of course the Sansui is no Day Sequerra

fwiw ymmv

These two prior posts nailed it.

What is the rest of your system? Have you actually auditioned the two units either at a dealer or at a buddy's place? better still, have you auditioned either or both of the units with your particular system? (i) without identifying and assessing the make-up of the rest of your system first; and
(ii)accepting that strong personal listening bias exists front and centre;

A blind purchase can quickly be regrettable and akin to asking:
Q: "... how long is a piece of string?..."
A: "... it depends..."

If I was to tell my boss something was impossible I would be looking for a another job. Anything is possible. I asked the question to get an opinion from someone who might have had a chance to A-B the Day Sequerra with one of the high end HD tuners. I myself have a Day Sequerra FM tuner and the Day Sequerra FM antenna. Recently I bought a Sangean to set up a small system in my garage. It sounds OK but not at all musical. But what do you want for $200.00. I would never think of giving up my analog system but with the HD tuners out there I was curious to hear what some of you guys think.

"If I was to tell my boss something was impossible I would be looking for a another job. "

yikes!

I was just hoping to shed some light that digital is pretty good these days but I see you really need specific information. Of course even the Day Sequerra depends on the signal fed by the station so a difficult question indeed.

good luck