Of the several I have, two are about all I use. One's a Plews manual. Takes the full sized grease cartridges. I swapped out the rigid tube it came with for a flexible hose w/the zerk end on it. It hasn't given me any problems, but it really doesn't get that much use.
The other is a beautiful little Swiss made Wanner 300-2. It was originally used in a Bausch & Lomb glass plant to lube machinery. When it was made surplus I nabbed it.
It pumps by pressing inward on the end of the body- like a 10-speed tire pump, but shorter. It is about a foot long when fully extended but it will pump w/as little as an inch of compression, so you can fit it into a space as small as about 6" and still be able to pump grease. The thing I like best is it doesn't take two hands to use- just center the tip over the fitting and push. The worst thing is the small capacity. The one shown below has an oiling tip, mine uses a zerk tip but otherwise looks the same.