The base choices are vinyl or woven acrylic. It is highly doubtful if any brand is still using actual canvas, but I never say "never" for RV stuff.
Vinyl is a solid sheet product, impervious to water and resistant to tears but rather heavy. It can be a solid color or modestly patterned. Vinyl sheet material does NOT ever require waterproofing.
Woven acrylic fabrics are light and offered in an amazing array of colors and patterns, but the material is porous. It is made waterproof with the addition of a fabric coating and sooner or later that coating will have to be renewed. How often? At a guess, 5-10 years, depending in the usage and exposure.
These days most new awnings and replacement fabrics are woven but vinyl is still a great choice for a rugged, low-maintenance awning material. I think you will find that most brands of replacement fabric are commodities, produced in major fabric mills but sold under a variety of brand names. There may be differences in the grade of the fabric, e.g. weight, tightness of weave, etc. Try to find the fabric specs when comparing brands.
Former owner of 2004 American Tradition and several other RVs
Home is West Palm Beach, FL