Hi Kentgirl,
I am currently on mirtrazapine too. I will be going back to the doctor in a couple of days as they're not doing much for me and I think I need my dosage increased (obviously this will be different for everyone). While I don't think mirtrazapine is directly helping my depression yet, I have experienced two side effects which I have appreciated: #1, I have found that mirtrazapine helps me sleep! I used to take a long time to get to sleep, and didn't sleep very deeply, but now I sleep like a baby, which makes me feel better in the day time! #2 mirtrazapine has given me more of an appetite. Whereas I never used to eat much before, and rarely felt hungry, since taking mirtrazapine I have a much healthier appetite and have been eating better, which (as well as the improvement in sleep) has given me more energy.
Obviously (like lightenup said) I think different meds work better for different people, but I think mirtrazapine is certainly worth a try, especially if you have experienced sleep problems or a decrease in appetite as a result of your depression. I haven't experienced any unwated side effects either, so I would certainly recommend giving it a try! :)
Good Luck!