[davidmanze]

"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.

  
 It's funny because I would not use any of those ....
 
"the Mercedes (insert model) is best in class" ........ or ..... "a top of the range model"

 ........ a lens is usually "top class" .....  

I preferred Klaus's ...... "a bigger question mark maybe around the handling though" ....... although I would have probably used "about" as opposed to "around"
Why did you put a comma before "though" in your phrase ...... you don't pause and then say "though" in thin air ! .........

   In the end English is a constantly changing language, in general usage, often it contains errors, some from fault, some from deliberate bumps to the human ear, most in fact, are regional ......... and let's not forget personal tastes .........  but a few are deliberate "twists".......
  ............ they are my favourites .....