[Brightcolours]

"but the RF 28-70mm f/2 USM L is actually relativel affordable" Relatively
"The materials and assembly quality are top of the class. " ... are top class.
"A bigger question mark may be around the handling though." In Spanish, question marks are indeed around whole sentences. Perhaps "The handling may be a bigger question mark, though"?

Nice review.

     
  Apart from the missing "y" ........ I saw nothing there that merited correction .....

You are slipping then.... ;-)

Materials are top class, a product like the lens can be "top of the class". A Mercedes can be both a top class car, or the model the best in its segment, top of the class model. A small but distinct difference in meaning and usage.