Well, do you have a problem with the slow cards not being fast enough? If you only shoot one picture and then recompose before shooting another, it probably won't make any difference to you. If you shoot lots of action where you depend on clearing the buffer out quickly, it is important to you. It mainly depends on your style of shooting.
40D, 20D, Sigma 10-22, Canon 50mm 1.8, Canon 17-85mm IS, Sigma 28-135, Canon 70-200 L F4, Canon 100-400 L
Canon s70 and an underwater housing, Olympus 770SW, lots of tripods, lots of flashes, and about 15 gross of flashbulbs