Recently I only bike for about 30 minutes every night, my beam setting is mid, and my X2 would need recharging every week.
The longest ride I had with my beam set at mid was 1 hr 45 mins before my X2 started to dim (with one flashing LED in the indicator). However, the light was not freshly charged, it was already used for two successive nights for about 30 mins set at mid per riding session.
I use high beam setting sparingly/ when needed. Mid is bright enough for me.