Quick question:

If a truck comes euiped with a throttle return device, does it still need a faild safe installed?

In my opinion, yes. If your batteries get low and you loose reception and you were at WOT, then your receiver will remember that and stay at WOT. The failsafe wan detect low voltage and return your throttle servo.

Yes, they don't do the same things.
For instance, if you go out of range, the servos stay at the same position they were at when the rx lost signal even w/ a trs - believe me that's a bad thing.

It helps, they cover different failures.

A throttle return spring helps if you lose power to your electronics, or linkages pop off.

Failsafe is for low battery, or interference.

Or if your TX batteries randomly fall out, or anything else bad occurs, that the TRS can't do anything against

nah man, when my transmitter bateries get low my servos just start going crazy and ive got throttle return, it sucks man, ive had to chase it down twice, and cathcing a monster truck isnt easy, i bet its funny to watch though

Im noticing several diiferent types of fail safe units, some work only with NicD batteries other say make sure throttle servo uses red positive, can anyone tell me wich failsafe to buy for an MGT?

the ofna, or venom failsafe will work

I've had many problems with the venom VST, try OFNA

I have the Ofne fail safe and it works great.