I've used the 3M PF but not the DP. It's a good product and I got about 6 months out of it (but not a daily driver so YMMV). Very easy to apply (wipe on, wipe off) and also works well on wheels to reduce brake dust buildup.
I have both 3M PF and DP PC.
3M PF last over 6 months, while DP only lasted me 4 months as pointed out by others.
So if durability is important to you, you may want to consider 3M PF.