Absolutely, great points on the PowerTap P1 pedals and SRM EXAKT power meter, as well as the more affordable Stages Power L meter. I'd like to add that when it comes to power meters, it's not only about accuracy and durability, but also about compatibility with your existing gear.
For instance, if you're using a Shimano crankset, you might want to consider the FSA PowerBox, which offers both ANT+ and Bluetooth connectivity and is compatible with Shimano Hollowtech II cranks. On the other hand, if you're using a Look pedal system, the Look Kéo Power might be a better fit.
Another important factor to consider is data analysis. While some power meters come with their own proprietary software, others might require you to use third-party apps like TrainingPeaks or Golden Cheetah. Make sure to do your research and choose a power meter that fits your needs and budget, while also being compatible with your existing gear and data analysis preferences.
Lastly, I'd like to caution against the allure of cheap, unknown power meter brands. As you mentioned, it's important to look for a proven track record of accuracy, durability, and support. While it might be tempting to save a few bucks, it's important to remember that a power meter is an investment in your training and performance. It's worth it to choose a reputable brand with a history of quality and reliability.
Happy cycling!