7D is now doing like 2054x XXX @2.35:1, at around maximum 77 - 82 mb/s in crop mode, but that crop factor is 5184/2054 x 1.6 = 4.038, that means that 7D will lose that wide angel side. To compensate, running to maximum 25XX x 1XXX will require the write speed over 110mb/s, which is around almost 50% more throughput than it is now. At 2.5k, it will acquire a crop factor like 5184/2500 x 1.6 = 3.3, so a ultra-wide lense like EF-S10-22 will get a horizonal viewangel equivalent to approximately 33mm, which will make 7D quite amiable.