[member=152775]arobwk[/member] the Hampshire is a modern breed and the Saddleback a traditional. So, the HP is a faster growing, leaner pig with very big hams. Often referred to as the lean rind pig and used as a terminal sire on some units.
The SB technically has semi forward/semi pricked ears not full ears that cover the face like the Old Spot or Lop.
The Hampshire I believe originated from Saddleback stock taken to America and improved. There are not many breeders in this country compared to other breeds. I haven't seen anything but pricked ears on HP's. Nor have I seen true pricked ears on a SB although with all pigs who have semi or fully forward ears litters can have more upright ears to begin with.
I have seen other colours rather than black and white in HP litters but not often. They always tend to have a very well defined band whereas SB's can have extremely narrow bands and the breed standard says the band can be as small as just a few white hairs meeting over the shoulder.
I certainly think the SB is much hardier as an outdoor pig compared to the HP.