When I was looking for a servo with the least amount of wiggle or free play for my DA 50 I called and talked directly to the tech and repair staff at Hitec. They recommended the 545. The reason being it has a 5 pole motor rather than a 3 pole like most less expensive servos.

The 5 pole means it will be tighter when at rest and also recenters more accurately. I have found them to be a good soloution and they only cost around 28.00.

Good luck

Gary