When it was announced, most of the Formula 1 community wouldn’t have bet a single penny on a competitive Red Bull-Honda relationship. Even drivers were a bit concerned, with Daniel Ricciardo leaving the team also because not willing to take the gamble and Max Verstappen, according to rumors, linking his contract renewal to a win in the first half of the 2019 season.
Honda’s return to F1 had indeed not being flourishing while cooperating with McLaren, putting the japanese supplier under a major pressure.

At the end of 2017, a Toro Rosso-Honda partnership was announced for the following year. With the help of Pierre Gasly, who had previously worked with japanese engineers in Super Formula, the Faenza-based team was used as a test bed for a quick and successful engine development.
Happy with the overall result, the Red Bull family put their trust in Honda as engine supplier also of the bigger sister team.
Straight away performance was quite there with a third place finish for Max Verstappen on the opening round in Australia. Since then, competitiveness has improved well, with great power deployed in most of the tracks, and reliability issues that became just a memory from a forgotten past.

https://www.motorlat.com/notas/f1/13836/in-toto-s-shoes-james-allison-leads-a-mercedes-full-of-flaws

After three race victories for Red Bull and two even more surprising podium finishes for Toro Rosso, team principal Christian Horner has no doubt left: “Honda have certainly exceeded our expectations in all areas. So, it has been a really very positive start to this partnership”.
All the team knew that risk was a thing at the moment of the agreement: “There were a lot of questions as to why we had made the move to Honda. I think very quickly, at the first Grand Prix, we achieved a podium. We’ve scored more points than we had at this time last year. All around, reliability has been strong, performance has been getting better and better”.

A falling-apart relationship with previous supplier Renault made the choice almost mandatory. In the end though, it seems like powers have switched between the French and the Japanese factories. In 2019, Honda has indeed scored its first pole position and first race win since 2006, and its first podium since 2008.

After this glance back to the past, let’s focus on the future with an optimistic Christian Horner: “The progress that has been made with the introduction of each engine has been great to see. Reliability has been strong -he said- This year was always going to be a transitional year in this first year of this new partnership but it feels like momentum has built through the year and with stability of regulations in all areas for 2020, we’re really looking to take the positive momentum from RB15, the current car, into RB16, which will be our 2020 contender”.

https://www.motorlat.com/notas/f1/13817/is-honda-currently-the-fastest-engine-in-formula-1