The tires are 23 mm on the Jamis, and that is a real skinny tire for big guys like us. If you get the Fuji with 32mm, you have the future option putting 23 mm's on it. You might not have the clearance on the Jamis to to put 32's if you find the 23's too skinny or harsh riding. I looked at the Jamis products a few months ago and almost pulled the trigger and got one.
I ended up with a Specialized because it had the fork and seat stay clearance for fat or skinny tires and fenders. There are no fender eyelets on the Jamis and I ride everyday except if it is sleeting or raining sideways.
However, that Jamis is a sweet ride and if you can get one for $600 that is a great deal. They were $900 around here when I was looking.
Get whichever one feels best, and like Tom said have the wheels hand tensioned. As long as your not jumping curbs and unload the seat when hitting rough pavement you should be good.