I use Photoshop so I would recommend it. I am not familiar with the Corel software to comment on, but I understand it is nice. Problem with new Photoshop is you have to rent it rather than purchase. Thanks for the comments.
Well, the plane was designed before Messerschmitt acquired the company in 1935. Also, all extant airframes bear the designation Bf 109 (with a few exceptions), which is the official designation. So, there really is no debate.