The Butterfly is the most contemporary looking vario I've flown with. All others look quite "old fashioned" after using it.
The multiple "pointers" displayed give a pretty complete analysis of the airmass at a glance. The wind calculation is the smoothest I've ever seen. It works very well in weak lift. I did not get to fly it in choppy lift.
However, Marc from Butterfly told me that the FLARM warnings in the vario do not cover the full range of warnings that the FLARM display does. Besides this I believe it does not automatically switch to the radar screen if there is a warning. They do not recommend it as the primary FLARM display.
Jim