George,
Yes, big chunky files are best and with today's cameras creating HUGE RAW FILES, great to have as a "problem"! On the other hand, I've sold 4 foot by 6 foot prints from much smaller files here!
As mentioned above, a 5700 dpi/ppi file will print out to 57 INCHES!! Or more, depending on the product here. Shower curtains and duvet covers as an example. And people here that know what they are doing CAN enlarge their images, I do it ALL the time, but terrible results if you don't know what you're doing!
Don't oversharpen and make sure your monitor is pretty close to being accurate, a few of you scanned desert images seem a bit bright to me, maybe 1/2 to 3/4 overexposed and one you have of a buffalo in a field, a bit soft. FAA will not print images YOU sell if they think they're not perfect! And that's a heartbreaker!!!
Rich