Both headphones offer solid battery performance, making them suitable for long listening sessions and travel. If you're comparing Sennheiser PC 31-II and Koss UR22i, both models offer a strong combination of sound performance, comfort, and modern wireless features. Impedance levels vary (32 Ohms vs 34 Ohms), which can affect compatibility and audio output when used with different devices. Both models support modern Bluetooth connectivity, ensuring stable wireless performance with compatible devices. There is a noticeable difference in weight (90 g vs NA), which may affect comfort during extended use. In general, both options are suitable for everyday use including music, calls, travel, and work-from-home scenarios. Both models feature noise cancellation, helping reduce background noise for a more immersive listening experience. Both headphones are equipped with capable drivers that deliver balanced sound output suitable for music, calls, and entertainment. The frequency response differs (40 Hz - 18000 Hz vs 20 Hz - 20000 Hz), which can influence how well the headphones reproduce lows, mids, and highs.

Verdict: Both headphones offer strong performance, and the right choice depends on your priorities such as battery life, comfort, and noise cancellation.