I had a 9250 die with the 401. I think I was just unlucky. You can still get the 9253 but if any of mine fail I will replace them with the 9254. I am not sure if it needs it but the 9254 does have more torque which would fill me with a bit more confidence.

If you are desperate to fly and can't get hold of a suitable digi servo then you could always put an analogue one on as a temporary measure (just remember to reset the DS switch to off). In this case a 3001 would probably work or a 9001 would be better. These are just suggestions based on specs. I have only ever used 9250 and 9253 on the tail. Only problem with this will be that you will have to re-do the servo and gyro setup when you switch back to digi (if you do).