By far, the most illuminating new thing I got out of it was traffic display. In the Bay Area, I'm always inside someone's "hockey puck", so traffic is fairly reliable. As you get away from populated areas, be aware that the traffic may be missing even if you have the ADS-B light lit. It's additional information, not the only source for traffic, no matter where you are. But...it's fantastic info.
Weather is the second thing. I'm a VFR pilot for now, so if you're routinely IFR, that may change. I like that the METAR is pushed up automatically, allowing FF to know which runway to plan for, often long before I can receive the ATIS or AWOS. I'm not a heavy user of the radar imaging, but, again, that's because I don't fly when and where it's most useful.
Like I said, AHRS...maybe if I flew IFR. VFR, it's a parlor trick most of the time. Maybe it saves my bacon one day, but probably not. If I fly into IMC unintentionally, I probably won't have the time or energy to bring that screen up, especially if I don't have the iPad in the yoke mount. (I often don't fly with it on, pulling it out just for chart work.)
Big battery and effective fan mean that it has only complained about heat once or twice. The 2S has a much better USB port than mine. I don't have the pressure sensor in mine, so I can't comment on that. WiFi connection is dead reliable, far more so than any Bluetooth-based device I've ever used.
One complaint is that the rubber power button can get lodged under the case. If it gets stuck there, the device flashes all red. It recovers easily, just by jiggling the button. However, it is exactly the same display as overheat, so there have been times I've moved it off the glareshield thinking it was overheating, only to find it still unhappy 10 minutes later. Check that stupid rubber button if you're having trouble. (Unless they changed it for the 2S. Box looks the same, but I haven't actually handled it.) You'll understand what I mean once you get the box.
