Personally i like my pm to be accurate and precise. I paid money for it, therefore i would rather have something that is better than the rest. I don't "need" my pm. My body is really in tune with my RPE and i can tell if my powermeter needs to be zeroed out or re-calibrate just by riding it and looking at the wattage and how my legs feel. I rode a ride where i got 3 mintues of power data total due to drop outs, and ever time the number came back on my screen it was the exact number plus/minus 5 watts i wanted to see. Even with my in-tuneness i would rather have an accurate and precise measure, especially so in 3 months i can look back and see real changes, not just slope related gains and losses.