Stock image file formats appear to be available only as JPGs.
This seems very limited for the cost of a monthly subscription in addition to my existing Creative Cloud package?
Have I got that correct, are there no PSD options etc
There is no PSD's. It is only .jpg for images and illustrations, .ai for vector. That's the way it is for any stock photo site. I am unaware of any Stock Photo services that provide PSD's?
Thanks for clarifying that, some of the images look like templates that you may expect to find a smart layer etc... But otherwise it's easy to use and the images are 300dpi etc