If you want a really big Jersey Giant, get it from a good breeder, not a hatchery.
My smallest hatchey Jersey Giants are smaller than the big Barred Rocks, and the larger ones are barely bigger than than the big Barred Rocks. Still sweet, good layers and very cold hardy though, just not very big.
They can get to be about 10 to 12 pounds, very friendly. They lay dark brown eggs. They are called Dark Brahmas. You might be able to see some if you check out www.rochesterhatchery.com
I would say Jersey Giant.
I have a black one I got early spring of this year and his head is about mid thigh on me, about 28" tall.
He pretty nice as well, real calm bird. Which is good, I don't think I'd want a 28" tall, 12 - 14 lb rooster attacking.