I need your expert opinions

For the Tuner there is always the "Tuner Information Page." A website deicated to tuners with rankings and commentary on a large number of tuners. You might want to check it out.

The Nak stuff is very good, the SAE not as much. I do not know the Yamaha.

I owned the C85 and the T85 along with an M85 at one time.
I would agrre with Viridan in that T85 is a very good tuner. But the C85 is a pre-amp that I never really did like. The parametric tone controls were just gimicky in my opinion. The quality of build was bad as the RCA jacks kept breaking, the plastic was very brittle and I had them replaced twice under warranty. Sound quality was mediocre at best. Now that said, it was MY experience and MY opinion based on ownership. Others may have had better luck and I mean no offence to those that love their C85.

This hobby is not about what others think. If you have listened to the pieces, and then want the opinions of others, that's different. Everyone hears differently, that's why there is so many different manufactures. They've all sounded good to someone. That's why they were brought to market. Let your ears decide!

plug-in, turn-on, listen, decide.

I owned the Nak CA5 (very minimalist) as well as the Yamaha C85. The Nak was an outstanding piece while the Yamaha was adequate. The Yamaha did have a remote though.

I owned both Nak and SAE in the past, so my choice is Nak on top for both pre and tuner.