The best suit fabrics come from fabric mills that have been in use for centuries. The wool comes from sheep raised in suitable climates like in Australia. The process is old yet highly perfected; fabrics are made in smaller quantities (rolls). There are numerous mills such as these that are situated in more or less the same areas – some are owned by brand name conglomerates while others are non-exclusive and sell to anyone.
In recent years, new mills have come on to the scene. These newer mills are prone to mistakes, therefore production of fabric is done in large quantities (1000 meters). The price differences between the newer mills versus the old mills is astounding.
It is important to realize that suit prices are largely influenced by where the fabric is made (and the brand name).
Here are some points to consider:
When buying a brand name suit (made from an established fabric mill), think about how much more you are paying for the brand name fabric. Consider a similar fabric made from a non-brand name fabric mill.
When a custom or made to measure suit is offered below $500, then the fabric may be of poor quality made from one of the newer mills that can offer bulk fabrics cheaper.
In the end you get what you pay for, a high quality wool with impeccable design will last you a lifetime (with proper care).