RE: 2008 North Sails = HEAVY!
I agree with what Andrea Cucchi says: once sailing, the weight feel depends on different things than phisical weight. Nevertheless, having a lighter sail is always good, during jibes in light wind for example, or if not else when carrying it.
Anyhow, miracles are difficult to make. Sails are made out of more or less the same materials, so lighter easily means less durable; exceptions being design peculiarities (think of the Maui Sails TR-3: heavier than usual, but the batten count is 1 or 2 more than competitors, in order to warrant extra stability) or excessive reinforcements or materials optimized for else than pure performances (think of North's white film: if really it is two layers of film kept together with white glue, then you pay that fancy white colour with mere added weight).