I've used one like this for over a year now. It sure gets the fluids down them. Only PROBLEM to me is, the design of the bottle. Who the heck in the product design department said "No it doesn't need a handle" needs to be horse-whipped. When it gets wet with milk replacer, electrolytes & the gel needed to lubricate the tube, it gets more slippery than catfish! I'm keeping mine, but I'm going to order one of the bag type now.
This is an absolute necessity for anyone who has calves. If you have a baby that can't or won't suck, this is how you can get those electrolytes into him without drowning him in the process. The balled end makes sure that you can't get it into the lungs, and insures that even a novice can provide this valuable care.