the service will be top class

[atakeris]

Hello,

I can assure you the service will be top class.

I can assure you the service will be of the top class.

I can assure you top class service.

Are they interchangeable? Is it necessary to put an "of" in front of the adjective if it goes after the noun?

 

[Copyright]

I can assure you the service will be first class.
I can assure you the service will be of the first class.
I can assure you of first-class service.

We don't use "top class" in this context.

 

[atakeris]

Thanks!

 

[ain'ttranslationfun?]

Right, Copy ( ), but mightn't the first mean that others will provide the service, and the third that you will? (We could also say "guarantee" for "assure".)