It's spelled Shiloh Shepherd. You can think of it as a large GSD, but there are differences in structure, appearance, and temperament. See their standard here: ISSR Shiloh Shepherd Illustrated Breed Standard
I know this dog, Starr
, and she is a very awesome dog. Temperament similar to the GSD. She has a great work ethic, very willing to please, and very good drive. She's quite a nice dock diver jumping over 17' more than a few times now. Other than her size, she's in many ways similar to how people here describe their GSDs. Starr actually changed my opinion of Shilohs. They are not all "lazy, fat, huge GSDs good for nothing but laying around." Starr is as active, if not more so, than many of the dogs here.
I'd not own based simply on their size. But there are some really nice ones out there.