I went the opposite direction to you, I had the ATP for a little over a year and decided I needed something deeper. I bought the T2 and was completely disappointed in it. The T2 was slower. much noisier, harder to distinguish targets.
I use the 8X5 DD coil on the ATP, excellent coil. I decided to give the T2 another chance and ordered the NEL 5.5X9.5 Sharpshooter coil. It made the readings much more accurate, detector is not nearly as noisy and actually a lot like the ATP.
I now use both about equal amounts of time. If I prefer a more relaxed hunt, I use the ATP. If I want to really clean out an area, I use the T2.
The ATP is faster and more comfortable to use than the T2. The T2 has a little more depth, is more accurate on ID of nickels and gold. Overall, the ATP has paid for itself a couple of times over. It will probably be a long time before the T2 pays for itself.
Good Luck & HH
PS: I have found very few items in places that I have already been with ATP. I think it would be the same result in covering places that I have already been with the T2.