I ´ve grown "uchiki kuri or hokkaido for the last few years and like them the best so far.
if you leave them on the vines till the foliage has withered, which in my case is about now, and make sure you cut them off with a 10 cm long handle attached, they usually keep till march or till you´re sick off them. no need to peel, dark orange flesh, good flavour, about 2-5 pounds.