It's dangerous to assign variables which share names with existing objects, especially commonly used ones like data.frame.
Most reading functions let you specify what class the data should be. That way, you won't need to convert it afterward.
Similarly, most reading functions let you supply the column names up front.
Many people frown on rightward assignment (->). If you're the only person who'll look at the code, then it's no problem. But if others will read it, they may not notice a variable's being assigned.