CSS or image for submit button?

What are the advantage and disadvantage of using both?

1. CSS

   <input type="submit" class="removeBtn" />
   
   .removeBtn{
       background: url(Images/Remove.png);
       height: 25px;
       width: 25px;
   }
   

2. Inline

   <input type="image" src="Conten开发者_Go百科t/Images/Remove.png" />
   

Semantically speaking, you should always use a submit button. A user with a screenreader will have no idea what the function of your image input is.

Edit: as per comments, the image button will automatically submit a form as well as an input with type="submit"