You will hear a lot of different answers to that question. A lot depends on the application and what radio you are using. Hightech and JR are fine servos, and there arelots of cheaper servos to be found. I've stuck with Futaba to make it easier on myself to swap parts from plane to plane. For most of my .40 and .60 sized sport planes, I've stuck with Futaba 3004's forcontrol surfaceslike ailerons and elevators that see the most input fromme and my style of flying. These have ball bearings and give a smoother and longer lasting operation with less current draw from your flight battery than a non-ball bearing servo. 3004's are suitable for use in any applicationon a .40 sized plane, but I use 3001's or 3003's for the throttleand rudderas these servos don't typicaly see as much activation and they are a little cheaper than 3004's.All of these I've mentioned are standard servos and are not the cheapest you can buy, but are among the cheaper servos. Depending onwhere you buythem, they are$10 to$20 new. I've purchasedmanyhere on RCU and E-bay at much cheaper prices andI've found them to be very reliable and easy to repair.

Ona3D or pattern plane in the hands of a skilled pilot, a precisionservo or one with higher torque and faster responseis often a better choice due to the larger control surfaces and the faster response needed.When you pick the plane you are definitely going to build, you should check for threads on that particular planeand/or ask more questions here for betterrecommendations.