We have used both. EGP does not have (if I remember right) wrong spellings/capitalizations/punctuation, etc. to have the student fix, DG does. We used to use DG and, when I posted ques. about it, Sonya shared with me how CM kept away from her students “seeing” the wrong spelling/grammar/punctuation. She did share that every family is different and that it isn’t “wrong” to use it. We did stop using it and went with another grammar product.
The format of the EGP I have is not friendly, to me. It is such a large workbook and having the answers on one side, student text to fill in on the other, didn’t work for me and the size of the text is just too much for a workbook.
They are both “fill-in-the-blank” or “underline the noun/pronoun,” etc., which is perfectly fine, we have just chosen to use other products.
HTH