In reply to kevin stephens:
I use both (Fuji X and Canon FF) and all things being equal there is an improvement in quality that is discernible before you get to pixel peeping. Various tests and online reviews would support this as well, but you need to ask yourself if you need or want that extra quality when it costs so much more both in dosh and in effort to lug around. The Fuji is superb in its own right, but the Canon is even better. Big cameras handle better too, which is significant if you are using them in testy conditions and maybe with gloves on. If your camera is fiddly you are more likely to think 'can't be arsed' and miss a potentially great shot.
Re lenses, if the reviews are to be believed, some zooms can rival primes across much of their focal range if not all. I'd go with what you prefer.
I tend to agree with Ben though. I bought the Fuji as a take-everywhere camera and more often than not I find myself suffering the weight of the Canon as it's better to use and more capable of dealing with tricky lighting conditions. This is for walking and cycle-touring mind, I wouldn't take it on anything other than the easiest of climbs.
Post edited at 20:27