Pros
The staff at PSG is honestly so kind and willing to help. You get to be set up with a mentor who you check in with every week and who you can talk to about your professional goals. They really treat you like a full member of the staff here, which is valuable as an intern where a lot of internships can give you menial tasks. They are always clear about how each task you're doing is going to help their overall projects with publishers.
If you have any interest in working in publishing, PSG is a great internship because you get to see a different side of the industry - PSG is contracted by the big educational publishers and works on a wide range of material. The office is small, so everyone really gets to know each other. I always felt welcome here.
Cons
Like most internships, this is unpaid - although you can get credit for it (I personally didn't; the experience was worth it for me). Sometimes, tasks can feel a little bit menial, but you will never be asked to do anything that isn't vital to the project. There can be slow days when there isn't as much work - for example, I was writing a lot of extra blog posts - but usually it's just because everyone is slow, and so everyone's in the same boat.