Hitec or JR digitals ?
All things have failure rates.... That said some more than other's, even the best products have these same failure modes.
I have been observing the noted purported failures of Hitec Digital servos recently and can only wonder... Why have I been so lucky... Myself and other's within our flying team have been using these servos since they were first introduced on everything from pylon racing Warbirds to 42% GS Aerobatic models. We have a vast cross-section of use. We have had great success with all of the Hitec Digitals. Primarily using the 5945 series and 5735 jumbo's, no failures of any kind to date... I am not talking about just a few of these servos, either I'd have to guess we have cumulatively well over one-hundred of these servos in GS models, alone. All of the models are subjected to regular flying and mainly 3D abuse... Additionally we're using both major names of radio equipment, again no problems with either set-ups.
To date I am only personally aware of three failures of which two were realized by me on the bench after cycling eight 5645's for around twenty minutes and another of the same installed on a model after about thirty minutes of flight time, luckily the servo was acting funny during the pre-flight and the model was grounded. I heard there may have been some QC issues with the motor's... The single servo was used on a Model-Tech Magic and the two that failed were to be installed on a 80" Extra, which was later done with new cycled/tested servos which now has approximately 40 flight's without any problems.
So , I can attest to the following with hands-on knowledge and lot's of flight time.
We have had zero failures with Hitec Digital servos utilized in our giant scale models, no issues at all.
JR-8411's numerous failures specifically, motors smoke, amps fail, pins blow out of the caps and lastly the gear train's suffered from pre-mature slop. Not to say that these are not good servos, I'm offering that they like other's have had problems. Those that suggest different have not used enough of them. Every time I had to send in 20 or 30 of these beauties I used to cringe at the thought of having to pay to repair them. Now that's changed with Horizon's new 3-year warranty.
Lastly it would seem for the most part that JR, Futaba, Multiplex and Hitec have evolved with the technology and hand's on exposure to failures to provide good quality servo's that can and do work well. I would not hesitate to use any of them on any model...
Obviously care and feeding of your servos and radio components is of paramount consideration. If you have any doubt of the ability and or reliability of any component test it, cycle it or have it checked out prior to flight....
Have Fun