Check out the hobbyking servo called xq power s4020 its not actually a hobbyking servo but listed as a hobbyking on their website.
I have the savox 1256tg and the xq power s4020 and haven't seen any difference except.
The savox costs twice the price and slightly stronger on 6v
The xq power is water resistant and can run 7.2v nihm and then it just beats savox specs.
Both servos are titanium . Alloy case . 25t spline . Coreless digital . Double ball bearing .
The plastic tabs on the xq might be brittle tho or it could be my fault but I didnt use the rubber inserts and over tightend the screws and snapped a little peice of the tab off one corner but its still gripping on the broken tab.
Theres not tons of information on the servo but a google will pull up many plane threads with people praising the servo for the price you couldnt get a used savox1256 either.
I only read about one or them burning out out of the 30 page thread with multiple buyers buying multiple servos and the burned out one was fitted to the rudder of a 100cc plane lol so it can be forgiven for burning out do that job by itself.
I had a xq power s5040d too in my fg marder and that was also flawless except one design flaw thsy could be a good thing but the spline was over sized like 8.4mm so it was very limited with servo horns but xq did supply it with a plastic double side and an alloy single side horn and again was $35 new for a 1/5 servo 33kg / .21sec water resistant . Alloy case . Titanium gear.
They are definitely worth afew google searches I will only buy these from now the newer servos they are doing are not cheap either so get on while they can still be found cheap.
---------- Post added at 7:22 AM ---------- Previous post was at 7:10 AM ----------
Heres the biggest thread I found on them.
http://www.flyinggiants.com/forums/showthread.php?t=62546&page=4