Is this the heli you have? [link=http://www.centuryheli.com/products/helikits/cn1000cHawkPro/index.htm?currentid=302]Hawk 30[/link] If so then it has a TT tail.

You may want to try upgrading the tail servo first, something faster and digital. I have a Detrum gyro on my EXI 450 (with a Futaba 9257 tail servo) and it does a decent job of holding so try the tail servo first and see if that makes a difference.

Mark