Is there a difference between using this.props vs props in React?

No diffrence.

props === this.props // true

Basically, it's same in this case, but if you consider the whole component then props can only be available if you pass props as function argument such as below example

componentWillMount(){
  this.someFunc(this.props);
}

componentWillReciveProps(nextProps){
  this.someFunc(nextProps);
}

someFunc(props) {
 ...... 
 // in here props and this.props are completely different
 as props is you latest props while this.props can be you previous props
}

while you can access this.props from anywhere of you component, i hope this gives you the idea

The rules for ES2015 (ES6) classes basically come down to:

In a child class constructor, this cannot be used until super is called.

ES6 class constructors MUST call super if they are subclasses, or they must explicitly return some object to take the place of the one that was not initialized.

So as the super(props) is called in the constructor. props and this.props are same. so,

props === this.props // true