I've never heard of liquicell technology. Sounds like a marketing gimmick to me.

This is the clearest answer I can give. Package 8 is factory leather. Every Prius that is Package 8 from the factory has leather.

Package 7 does not come from the factory with leather, ever.

That means that the dealer is having leather put on the seats of Package 7 vehicles when the vehicle arrives, or the regional management is putting leather on those cars at the port. GST and SE regions do a lot of non-Toyota port upgrades. Most other regions do very few if any port upgrades.

Factory leather is your best bet, so Package 8. Aftermarket leather can be very well done, if done by experts. There are folks who have had aftermarket leather installed prior to delivery and it has been done very well. And others have seen it done very poorly. There isn't a whole lot of QC when leather is not installed by the factory.

I'm also pretty sure that the leather the dealer is suggesting on the non-equipped package 7 can be done at a later date through a shop you choose and to your specifications for at least a few hundred less than what the dealer is charging you. Call some upholstery shops and see what they say and compare their quote to what the dealer is charging for non-facotry leather.

It has been said:
Hybrid drivers come in 3 flavors, greenie, techie and cheapie. Pick any 2.
2005 Prius, Melinium Silver over gray, package 5 (AI)