Hitec HS 65's
 

Pros and cons for MG against HB ?

Skaliwag, I never have tried the MG65s [they seem kind of new to me]. I noticed they are heavier and more expensive.

The Karbonite servos have really performed well. I stripped gears once while flying .15 powered 3D with a huge rudder and lots of throw doing spins, then reversing the rudder full opposite. Basically being stupid and destructive. The servo hung in there for a few flights and now I have an idea about what is too much for them. I use them in all the racers, but they use very little control throw. Vibration would be their biggest enemy but so far so good.

I love these little servos and recommend them. i have never broken one inflight like CP has only in a crash. I had one of these mounted in a Great Planes revolver. This plane had a Saito 91 in it and th little HS65 servo was mounted on the firewall with a short 1" push/pull rod. well the firewall broke loose and all that held the engine on the plane was the HS65 servo. the engine stayed running for 15 minutes or more at around half throttle. those gears held up fine and I am still flying that little servo.

These are my favorite little servos. oh and less slop over the HS65MGs

I've read negative comments about Karbonite gears somewhere but I think it was with larger servos. It could be that Karbonite material's "Sweet Spot" for application is with the micro servos...?

Well the karbonite gears in larger servos are much thinner than the ones in the HS65. look at a replacement set and you will see these are very thick.

Check out an HS-45 sometime, the gears look huge for the torque rating. Even the HS-35 gears look decent, to my eyes at least.

I have seen written more than once that plastic/composite gear trains on servos tend to have less backlash. Airraptor sounds like you have already found this to be true on the HS65's.