Yes the Lock and Lube grease coupler is a little pricy, but when figuring in the aggravation it solves with when greasing dozens of grease fittings time and time again, then the cost is not so bad.
I liked the Lincoln grease gun I had few years ago better, it had two speeds, but it's another battery and charger that dont fit nothing but that grease gun, what good is that. With Dewalt 20v, the batteries fit all my other tools and I have several, so if in the middle of greasing the battery runs down, just take the one from the 20v hammer drill, oscillating tool, sawzall, 6-1/2" circular saw, jigsaw. I have 3, 3 amp hr. batteries and 1, 5 amp hr. battery for the circular saw. Yeah I is a Dewalt fan, also my son bought the new 20v Dewalt framing nail gun last year and he loves it.