Absolutely no problems with PSD either way - in or out.
If it can be drawn, Corel can read it. Well, if not, then it's obscure and Corel still reads extinct stuff too.
Corel is to Photoshop as the Atari 800 was to the C64. Better product but the opposition had the better marketing.
Atari realised that and bought the Commodore marketing team. That's why the Atari 1024's sold better than the Amigas - although the Amiga was better by far.
Photoshop's problems are/were the interface and handling. Photoshop wins because it is probably the most pirated piece of pro software on the web. I even dare suggest that many FS repaints are made on PPS (the extra P is a politically incorrect "P for Pirated
)
Oh yes... another of my AKAs is "The Kitchen Cynic"