Not ridden an SA-T but had a 2008GS and have ridden the variants since (except latest 1250)
I have had an 1190S and 1290S (well still have both) and for a while had a 1090S alongside the 1190 - and would of preferred any of them over the GS of the time, even the "budget" 1090 as it was still a lot more exciting than the GS - and IMO they all outhandle the GS, and the brakes on all of them are more than good enough to get the ABS kicking in on a good road with two finger braking - what more do you need than to have brakes that have excessive power and 50% of available effort...
...and they don't leak from new either!
I do agree about the bullshit people like to buy into, my 1190S is better on rough roads than the 1290S, the 1090 almost certainly had the sweetest handling when thrashing it like a sportsbike, but the GS semi-active suspension equally misses the mark, the latest with auto ride height (preload) made me feel sea sick as it constantly pitches back and forth trying to balance itself out, it was like being on a rocking chair when trying to cruise at a steady speed, and it's "comfort" mode had zero damping, nothing comfy about still boinging up and down 500 meters after the bump that started it al off.
Ignoring the unwanted electrical interference on the suspension and the lack of adjustment (in that there are only 3 modes one fella at KTM liked) the 1290S is definitely the best "Sporty Adventure Touring" motorcycle I have owned - and another problem is bikes have become so diverse it is not like the old days of a which 600 or which 1000 should I buy.
I guess the 1290T was pitched at the GSA, but the 1290S competes with the GS, but is not trying to be a better version of it, it also competes with the S1000XR (but so does the Superduke GT) and it competes with the Multistrada which is much further removed from a GS competitor and more like the XR, yet in some ways less like the Superduke.
It seems there should be a bike for everyone, except me, as I want the 1290S with quality manual suspension of the 1290R (but without the skinny wheels and extra 2 foot of height)
The 1290T never lit my fire, the electronic suspension was a put-off and the extra torque of the 1290 mill was not enough, although with the cruise as well I might of been tempted - if it came in any colour other than white, but I really do not want the extra weight, and the 23L tank of my 1190 / 1290 gives an easy 200+ mile range even at French Motorway speeds with 3 boxes weighing it down, and easily over 250 if obeying the French 50 mph national speed limit.
The 1290S/R make much more sense to me, who would want all that weight off road? and with the later 1290S/R having the cruise control, cornering lights, TFT, Keyless etc it makes for a better touring bike (IMO)
FWIW MCN did name it "bike of the year" in 2015, but I rarely agree with the bike press on anything, especially the "BMW Bribed us to say the GS is the best adventure bike for the 10th year running", I guess KTM opened up the advertising budget for 2015.
I have seen some excellent value 1290T's in dealers and thought them to be an awful lot of bike for the money,