title: Use separate images or setImageEdgeInsets?
body: <p>I have a button in a tableview cell.  The tableview would typically hold 10-30 cells.</p>
  
  <p>Depending on a user setting, the image on the button can be displayed at a different size.  Note that the button itself will not change size.</p>
  
  <p>I can achieve this using a single png image and adjusting the imageEdgeInsets, but is this the best practice?  I imagine it is not particularly performant.</p>
  
  <p>In similar situations, is it normal to create, say, three version of each icon in my application to handle the different view settings?</p>