im finnaly done with my trainer and going to be getting a sig 4 star soon.

iv already planned out to get the tt .46 pro and was wondreing if it would be fine to use my old servo and radio. I have not crashed the plane, but the radio/servos are 4-5 years old.

they work fine on the trainer but will they be fine on the sig.

im using the airtronics vg400 radio, with stock servos

also what size prop

Your radio gear should be fine in that plane.....just make sure your batter is still in good condition.

I find that an APC 11x5 prop works great with the 4-star/TT Pro .46 combo.......The plane still has good speed, great vertical, and it floats less and slows down better on landing.

I would leave the trainer intact- 4 year old gear best belongs in it- Besides, now you can do things with your trainer that you would never do with other planes.

Having a trainer in the hangar is always a great idea.

I agree, if you can afford a flight pack, buy a new one for the 4*. You may still want to fly the trainer on and off.

If you're sure you won't want to fly it again, or can't afford a new flight pack right now, your original servos will work fine.
Dennis-

Although it is a good excuse to get a new radio.

The fact that your radio is 4-5 years old is not so significant. What's really important is how much use has it had. If you've been flying a couple times a week for 4 years, then it would definitely be good to invest in at least a new flight pack, if not an entirely new system. If you've only flown 10 times per year, then the thing is just getting broken in. As has already been mentioned, check your battery capacity. If the plane and radio are in good shape, you may be able to sell the whole setup, minus the engine, to a beginner and use the money for a newer radio.