@centre, Yes - I really like the Teeter FreeStep cross trainer. I use it at least 30 minutes a day, sometimes longer. You can adjust the tension so that it is really easy to use with the arms and legs, or you can crank the tension up so that it takes a lot more effort with the arms and legs.

Sorry to hear you have patellar tendonitis. I originally got the Teeter FreeStep to replace my recumbent exercise bike to help build leg strength after I had a knee replacement. I also bought an inexpensive Row-N-Ride machine that lets you easily do squat type exercises which help with cardio and leg strength. 10 to 15 minutes is about my max time using it as it uses your body weight and takes more effort. https://www.amazon.com/Sunny-Health-Fitness-Row-N-Ride-Trainer/dp/B08SSFZN4P/