my first job ever did this. qa and customer support were combined which made it the best place to learn all the ins and outs of a very complicated product. after 3-6 months i had excellent knowledge of how the product actually functioned on the ground and how the customers approached it.

highly recommended as a training scheme! especially in cases where engineers have a lot of influence on product design.

(although, in a high volume ticket oriented environment, or a highly structured testing environment, the benefits fall off dramatically. the big value was setting things up from scratch in different contexts and seeing where people struggled)