Slowdown on the Lumia 1520 with WP 8.1 Dev Preview

Anybody else noticing slowdown on the 1520 now that you've got 8.1?

1. I'm seeing an almost imperceptible lag while typing in Messages after using the phone for a few hours. Just feels like it's running slightly behind my taps.

2. I'm also occasionally seeing the phone get stuck on Glance or a black screen when hitting the power button, finally unlocking after 15ish seconds. If I hit it once or 15 times, it just doesn't respond to the power button until the time has passed.