Tidal HiFi Test - how representative?

To anyone who has taken the Tidal HiFi Test and also subscribes to Tidal HiFi, how representative of actual sound quality is the HiFi sample compared to what you hear as a "premium" subscriber? Are the differences between the A & B samples used in the test indicative of the improvement in SQ subscribers enjoy?
The enthusiastic Tidal advocates posting on A'gon have certainly got me curious.