I still have the original Varia unit. I wish its light was brighter, but until it dies, I'm keeping it. The changing flash intensity is also great notification for riders behind me in group rides (they've learned that a car is coming up from behind when the intensity changes). My closest riding friends actually have their head units connect to my varia as well so that they get notifications on their screen if they're close enough to me (10m or so...)

I ride mainly country roads, so the Varia is great for me as traffic is not heavy. Probably not much value in highly trafficed areas as it will always be set off.