I've ridden quite a few different models before buying the AT and the only one that I really liked (besides the AT) was the Multistrada Enduro.
It has a very charismatic engine and the steering is really nimble
Than again it's bloody expensive and I didn't really feel connected to the bike.
I've had the same feeling with some other bikes like the tiger 1200 and 1200 GSA where the different riding modes, complicated traction control, wheelie control... make it feel to digital, where bikes like the AT and 800 GS feel more analog.
It feels more like 'what you see is what you get' and I personally like that.
You know the way the throttle will react and where the strong points in the rev range are. Just like you know the way the suspension reacts in every condition.
That way you can always react accordingly, without being unpleasantly surprised by the way your bike behaves, because it's in the wrong setting.
To me the engine and ergonomics of the tiger 800 made it feel like a naked bike rather than an off-road or touring bike. The engine has a a great sound to it, but when you're accelerating, just at the point where you think "wow, this is great", the rev limiter kicks in and you're left a bit disappointed.
The tiger 1200 felt heavy and slow when maneuvering and trough slow corners, but it has a fantastic engine!
Overall I haven't had the slightest doubt that the Africa Twin was the right bike for me.
The engine has a ton of character, the steering is light and nimble, the ergonomics are perfect for touring and commuting and you can have so much fun trowing it around and wheelieing without having the feeling that it's to much to handle (most of the time).
In the end I guess it's completely subjective, which is why I'm really happy with my AT and the other guy may be trilled with his GS.
Perhaps if my last bike wasn't a varadero but a speed triple, I would have ended up with a tiger 800?! Who knows...