This is a tough one and depends on how well you know your Elite, if you know it well you may see some advantages with the GT, if you are having problem with the Elite you probably wont see a difference in the GT.
The GT put the controls back where they belong as the Elite were in the wrong spot for me and many others. The older Sovereigns had them in the right spot, but the Elite was changed and now on the GT they are back where they belong.
The GT has a toggle switch for silent search if you want it and find if you are in a area where targets are far a few this is a nice option, but for reg detecting I leave mine off so I have a threshold.
The Auto track is only used in all metal mode and i find the GT like all the Sovereigns work better in disc myself. The GT has a better rod set up over the Elite. The Elite comes with a meter, the GT don't, but the GT has a rechargeable battery and charger the Elite didn't. The meter for the new GT is different and will not work on the older Sovereign or the older Minelab digital work on the GT I been told.
Now for my honest opinion on the Elite and the GT as far as performance. When I went from the XS2 to the Elite I found many of my targets were not as deep as they sounded to be and thought maybe it was just the difference in the coils, so i put on my Coinseach coil and felt it was better, but still these target sounded deeper than they were. I felt like you do on the surface clad as it didn't seem to lock on as nice too, but did see on the smaller targets the Elite seen them a little better as I seen more smaller targets with the Elite.
Now with the GT I find I still get the smaller targets good, but also see i get fooled a little more on rusty iron, but see where I can tell the difference by comming at the target from a differnt angle. I also see that my target are sometimes deeper than they sound so I feel the sensitivity is a bit better with the GT, but like I say if you don't know your Elite well you may not see the difference. I also see that I have yet to dig a deep target I couldn't get my Sun Ray DTI meter to lock on or give a 179-180 on, maybe I haven't went over one yet that is too deep.
My opinion is if you really know your Sovereigns well you can see a difference in the Elite and the GT, or at least I can.
I also hunt with the Explorer XS II also and it is a very powerful detector and a very good one too, but I can do better coin wise with my GT I had in a days time. The Explorer will go deeper i feel, but I dig a lot more trash that is iffy compared to the Sovereign GT.
I too have been very curious on the new T-2 and considering trying one too. I tried the X-Terra 30 and 50 a little before freeze up and still have alot to learn, but it was impressive too.
Rick