I’m running my W3R3 tomorrow, and looking forward to it! Really pleased with R2, those 3 min intervals were still challenging, but in the end I felt like I still had energy for another set. And my HR is way better than the first two weeks.
I’m actually enjoying 3-min runs more than 90-sec ones, I think because they give me time to settle into a nice rhythm...
Also, after my app failed me a couple of times, I got a customisable timer from the App Store and set all my intervals with my favourite songs. I noticed that the choice of songs matters, some are way easier to run with than the others!