Hi easye,
Dojo is right, Core has a 2 year duty cycle on each model they release. The newest version of the Core range is the GTS which supercedes the GT which has been out for two years now and has served faithfully.
The XR has another year before it will be superceded and frankly, doesn't need upgrading as it is still a top kite. The GTS doesn't supercede the XR, they are two very different models.
A 2 year duty cycle allows the designers and test team to really go to town on developing and properly testing the products they produce. Think about it, Core release only one kite per year in the same time, most other manufacturers are releasing 3,4 or even 5 models per year.
Is there any wonder that the Cores have so little warranty comeback, or complaints about flying quirkiness

Their designs are tested to death
before release
I believe Ozone are also moving to a 2 year duty cycle for some of their models.
<begins rant here>
It is my opinion that the entire industry needs to adopt this policy, that way we get:
-Thoughtfully designed and thoroughly tested kites built to last.
-No need to upgrade every year to the latest model for fear of depreciation and the perceived need to have that little extra something.
-Kites will hold their value for twice as long. Resale value will be same but you will double your hours of fun per dollar spent ratio.
-Allows time for real improvements, not just changes for the sake of something new every year.
-Will reduce, but not eliminate the "flood" of second hand gear onto the market which will shore up the second hand pricing.
The industry has been advancing so quickly since it started and has borrowed much technology from sailboarding/paragliding/wakeboarding and surfing to rapidly approach the peak design plateau in just several years whereas surfing/hang gliding/windsurfing etc has taken decades to evolve to the same position.
There are few, if any, radical improvements to design nowadays, with the odd good ideas coming out from time to time. Many companies "borrow" <see copy> design improvements from each other so all we are getting is regurgitated, renamed and over hyped modifications rather than worthy original design breakthroughs and leaps forward in performance.
Improvements in designs are often only minor tweaks and there are even cases where previous years kites were better than some new releases for some manufacturers. Some companies still offer modest improvements each year, but there are many who's new kites performance is questionable. This is a disgrace and is caused by the designers being under immense pressure from owners to produce a new swag of improved kites ever 12 months. I empathize with designers workloads and wouldn't want their burden for any money. Produce a good kite and an improvement is
expected next year (and every year after that). Produce a dud, and they cop it from every angle despite giving it their best efforts.
Wouldn't it be nice if our new kites really were improvements rather than just different? The moment the industry adopts this 2 year design cycle, the better for everyone in the industry and of course for the riders themselves.
<rant over - too much coffee this morning>
KH