A usage of "ever"

Hi,

Could you tell me if the following dialogues sound normal to a native speaker?

Do you ever use the word "ever" this way?

Someone: I put your computer through its paces and discoved that it crashes an awful lot.

Me: Does it ever!

Someone: Your brother is rather dim-witted

Me: Oh, boy, is he ever!

I intended to use "ever" to reinforce my ardent agreement with my interlocutor's statement.

Thanks !