I took the DAT twice, first time I went through cliffs ~2x's and did a Kaplan course, made an 18 on bio. The second time I went through Barrons 1.5x's thinking I'd switch it up, but the style of the book just didn't fit me as well. It's true that cliff's is more dense and probably more dry (harder to read), but I tend to prefer bullet points, so that style fit me better. After doing Barrons 1.5x's very early in my prep (so early that I probably forgot it all), I did cliff's 4-5 times through and made a 22 in bio. Those #'s are greatly skewed by the fact that the 2nd time through I was much more motivated and changed a few tactics to improve my efficiency, but...just thought I'd share my 2 cents.
Both books lack a few details that the other book has (Been like a year since I was in the DAT game, but if i remember correctly i think Cliffs had better reproduction/embryology and too much plants, and I think Barrons had better bone stuff but really lacked in plants)
I would recommend doing both if you can, and tossing KBB aside EXCEPT for their practice questions/exams--I found those helpful. Also do DATQvault, another helpful question bank.
Good luck!