For better and worse, the PT quick attach plate is smaller and lighter. That's great for maximizing capacity. Adding a "standard" skid-steer plate shaves 2-300lbs off the load capacity, and perhaps more since the attachments have larger plates.
What you give up is lateral strength and rigidity. For me, and I suspect most PT owners, it is an easy choice.
If a skid-steer or a dozer could what I need, I would have bought one. For what I need, the PT series is unequaled globally, except perhaps for the Swiss Aebi, which is out of my price range, but it is a personal decision that come down to very local needs and uses.
All the best,
Peter