Good info I think.
I've read the info on that wheel again (now that I've had a couple cups of coffee) and it says the wheels are for trailers. Would there be potential for lower quality construction based on trailer wheels typically not being concerned w/ balance?
Another pro for the 19.5's would be longer life cutting tire expense and next time you won't be out the cost of wheels.
I was going to call them about the "trailer" thing, but I cant get over the weight! they would add 240# to the rotating mass. Getting up to speeds and braking must be negitively affected along with MPGs, but hey Im no expert if someone else knows different let me/us know.