Re quince: A very very ripe quince may fall apart with cooking, most keep
their shape unless actively pureed. Their juice and puree tend to be very
smooth or syrupy in texture as they have a lot of pectin. In many ways they
are pretty appley, but with aromatics all their own. There is a recipe
book called Simply Quince which doesn't address varieties, but will give
you a good feel for cooking with them. Other pie recipes will suggest a
quince in one pie that is otherwise apple.