Mark, the servo I used for the rabbit is a futaba 3003, torque 3.2kg/cm and works well because of the counterbalance at the bottom of the rabbit. FYI - check these cheapo servos 5.1kg £12 though as you say, high powered ones = high £££. I have one of these and am going to use it in my larger target which is coming along well!

Youtube link to servo moving target up and down, please note the rod with the spring on is actuall fixed for the video so disregard the spring and imagine just the servo, metal bar and rabbit. I filmed the other servo too just to show you it moving the magnet out of the way - this is the way I set it up as I said in an earlier thread. Hopefully the servo thing will now make sense.

Calv