Familiarity: I've used it once or twice and have initial impressions
After determining that the Assosoires Winter Gloves couldn't cut it for me below the mid-40's, I tried these... and they're terrific.
No glove will solve for poor position on the bike (that puts too much pressure on the hands) or for clothing not suited to the temps. So assuming you've got those things buttoned up, these gloves should take you comfortably down into the 30's.
Only issue I have is that I straddle the recommended sizing between L and XL. I opted for XL, thinking a little extra space inside might help with the insulating properties. But I would have liked to get into the L; as some have said, tighter gloves make you feel like you can go faster ;-) (Ha!) I just hope they don't somehow stretch out over time.