For demanding printers requiring long-lasting archival-grade images with a wide color gamut, this GALERIE Prestige Fine Art Rags Discovery Pack from Ilford features 5 sheets each of:
Smooth Cotton Sonora 325 gsm
Matt Cotton Medina 320 gsm
Textured Cotton Rag 310  gsm
Smooth Cotton Rag 310 gsm
Cotton Artist Textured 310 gsm
This allows you to test out different types of paper in order to find out what works best for your needs.