Naim Nait 5i with Tetra 120u's

I don't know Tetras, but you will not gain much, except full remote, changing your amp. As much as I love the Nait 5i, Blue Circle makes killer gear too.
I would get a Rega Apollo for music and keep the Oppo for video.

Have you compared the Rega Apollo to the Oppo? I've not heard the 970, but I recently bought the 980H and am still in shock.

Although I've not heard the Apollo, I used to own a Planet 2000 and IMO the Oppo is better. Going from memory mind you, but my point is that IMO the Oppo can run with many decks well beyond their meager price.

Have no idea how they do it.

I have the Oppo 981 and Rega Apollo. Rega takes it, obviously on CD only.
Sorry but I am not totally in love with the Oppo. It is good for what it is, a $200 universal machine, but rather flimsey and not always reliable.

FWIW, Oppo itself says the 981 does not match up with the 970 and 980 for sound quality. not saying the 970/80 holds up against the planet, because i've never compared... but i find my 970 to be a quite satisfying -- and exceedingly reliable -- little giant.