I'm a longarmer too! I've had my machine almost 2 years now and LOVE IT!
My machine is the HandiQuilter 16 with stitch regulator and have not had a single problem with the machine.
As far as skipping stitches I would change the needle, check the bobbin tension, check the needle tension. You might want to try a different bobbin, on my machine if my bobbin isn't wound well I will get skipped stitches.
What machine do you have? You may need to re-time the machine if it's been setting for a while.