How do you know if you are upgrading your DAC?

not all hot brands of dacs are made in china

not by a long shot

how do you define ’hot’? views of clown reviews of sub $400 dacs on youtube?

Advances in tech, lower cost to make a good Dac has brought more units and brands to the marketplace.
Some of the "hot" Dacs are from US companies who have the Chinese do their manufacturing. I've noticed the well known high-end audio brands are using this business model now.

Here are some of the popular and well built Dacs:
https://www.lineartubeaudio.com/digital

With limited brick and mortar stores, many online manufacturers offer 30 day trial periods. 

I went from an Oppo 105 to a Mytek Manhattan I a few years ago.  Same DAC chip but no comparison-the Mytek blew the Oppo away.  Suspect you can find many dedicated DACs with the same chip as the 205 that will similarly outshine the 205.  I eventually moved to a Bryston DAC3 featuring an AKM chip.  The Bryston and Mytek can both be easily had from Internet dealers (Audio Advisor, Music Direct, others) that have full return policies, and both are made in North America.

The only sure fire way of being sure you have upgraded your DAC is to buy a turntable and compare. The better the upgrade the more it will sound like a record. That's how you tell.