Lumia just goes on and on.

Just had almost 6 days use from the phone out of a single charge, and only had to charge it as a 'just in case' measure because of a potential medical emergency.

Charged it last Sunday evening, disconnecting it around 10pm, using it as normal to make calls, take a few work-related photos, send texts & emails, do a brief bit of navigation, a couple of min surfing. Plugged it in around 2.30pm this afternoon with 10% charge showing, which was probably good until Sunday morning without serious use.

Performance wise it's not a ball of fire, and Microsoft's interface is somewhat clunky compared to vanilla android, but I'll accept that trade for this kind of longevity and the fantastic call quality.