Yes, it's true that the covers are all the same, as far as I know, and I think they are all paperbacks too. From what I can tell they are facsimile but "good" facsimile type editions, so I would say they're better than SWRB. Sometimes SWRB reprints materials that are very hard to find elsewhere which makes them worth getting, and the same is true of Kessinger.
One way to get a look at the inside of a Kessinger book is to search using the Google book search function:
http://books.google.com/
Enter the search term 'kessinger' and you'll find many Kessinger books to view. You can look at the table of contents, title page and search for a word inside the book to see what the contents look like.
Hope this helps.
__________________
Andrew Myers
Husband of Jessica, Father of Jackson, Katie and Samuel
Member, Presbyterian Reformed Church of Northern Virginia
Warrenton, VA USA
Editor,
The Matthew Poole Project
"Let your Morning Thoughts, and your last Evening Thoughts, be what shall become of you to all Eternity." -- Matthew Poole