Gotta agree with everyone else that this is a fantastic tool.  Works really well.  This was my first time using a powered caulk gun and I was able to immediately use it like a pro.  Loaded a Liquid Nails sublfoor glue cartridge, dialed in about 25 psi, and laid a perfect 1/4" bead, very quickly.  Didn't have to wait on the gun, and didn't blow my fingers out squeezing.  A quality machine and for a great price.