The Mountain Standards review team at Alpinist Magazine recently put the Grivel Lambda HMS twin gate carabiner to the test. While it didn't get the highest all around scores, it did prove to be excellent at exactly what it was designed for, building anchors and belaying with a tube style device.
From the review:
"In a tube-style belay device, the Lambda's roomy curves and auto-locking assurance performed beautifully"
"The bent gate made it easy to clip the rope to crucial pieces of gear, and the 11 kN minor axis rating means the 'biner could hold the biggest fall I might ever take, even cross-loaded. It brought some highly sought-after peace of mind while I was building the anchor for a hanging belay from a tenuous stance."
Read the full review here