Testing the 128gig 1050x and comparing it in performance with the 64gig 1000x and also a lexar 32gig 1000x
Used 5D2 and 7D for tests.
Verdict.
If you are using a 7D, you can use the 128 1050x and be able to do 99% of the resolutions that the 64gig 1000x can.
If your using the 5DmkII, it is consistently 1-2 resolutions lower.
So for instance:
64gig 1000X ------128gig 1050X
1X normal mode
1728x972 16:9----1728x864 2:1(with GD-OFF)
1856x928 2:1-----1856x790 2.35:1(gd-off)
3X crop mode
2048x872 2.35:1--2048x820 2.50:1
1920x872 2.20:1--1920x804 2.39:1
On the 7D both 64gig and 128gig can do similar resolutions for continuous recording.