I use it for Max, when I first started I had to crank it up to 7 or 8 to get enough blood, and was still getting frustrated, so finally I just took the cap off, dialed it back to the lowest setting and use it that was. So basically I'm half free handing it, and half using the spring load so I don't chicken out and "pull" the poke.
The spring loaded action and the pen itself gives me a little more stability to when poking, but I can see where I'm poking easier without the cap on. Trying to free hand it the lancet was just too little to hang on to while wrestling Max and trying to keep the other cats out of the way. So this way I have something reasonable to hang on too, and still get a nice quick poke to the ear.
Hope that helps, Oh and don't forget to warm up his ear first it really really helps alot.
Mel, Max & The Fur Gang