Petzl Grigri 2

Excellent auto locking belay device.

The Grigri is ubiquitous, you see them everywhere you go, and for good reason.  It's just about as good as a belay device can get for toproping and sport climbing.  It's expensive, but worth the price in the end for the ease of use and the peace of mind.

First, it's easy to use. It has engraved simple instructions on the side of the device, and it's easy to see how it works with the locking cam if you pull up on the climber's side of the rope. Just run the rope through in the indicated direction, swivel the faceplate into place, lock with a locking biner to your belay loop, and it's ready to go. The way Petzl has designed it makes it practically impossible to close unless the rope is correctly run through the device. It's a simple device, really.

Although it was expensive ($74 on sale at REI), it lives up to the hype. I'm a beginner rock climber, and when teaching people or dragging them to the crag with me, it gives me peace of mind that should their attention lapse when belaying me, I won't be falling to my death. It's no excuse for lazy belaying or taking someone without proper instruction, but being on the wall knowing that in the event of a mistake or accident, the Grigri will auto lock.  

Construction is good, I wish they would have foregone some of the plastic on the device and opted for all metal construction. There's not much plastic on most climbing gear, and although they've used a decent plastic and in non-load bearing parts, it just doesn't feel like the most quality piece of equipment. I've used mine quite a bit though, and banged it on rocks while hanging from my harness, and it looks like it's holding up fine.  No major complaints.

I've used it for several months, toproping and sport climbing in mostly hot and dry Utah conditions.  It's been great.  I was on the fence about this, thinking my ATC was just fine, and after using it, it instills just a bit more confidence to whoever is climbing that they are safe, just another redundancy.  It works well, and is worth the price absolutely.  Ease of use goes to an ATC, but overall safety, I'd give to the Grigri.  It's also great when you're belaying someone who will be hanging on the route a lot, as you don't have to be providing tension to keep them on belay the entire time.

Great belay device.

Ease of use: 

Very easy to use.

Difficult for left handers.

Makes belaying more relaxing especially when the leader sepnds heaps of time falling or just hanging around.

Features:

Auto locking belay device.

Construction and Durability:

Very hard wearing. Never heard of one wearing out ever.