I would change that to read:
you can do anything with photoshop or the GIMP.
And then I would agree 100%, as long as the following clause remains:
However, if time is a factor, one can make a lighted dungeon corridor with special effects with CC3+ and DD3 in substantially less time than it would take to create exactly the same dungeon corridor with Photoshop or the GIMP.if you're willing to put the time in