Ok just put the Evo 3 through my club's first race meet for the year and it survived!
The key to protecting the diff gear is to shim the one-way using spacers between the bearing and one way axle. I used a single 0.1mm 10mm spacer.
Another thing to watch out for is to ensure that you use metal thread screws to replace the tapping screws that hold the gear case. The tapping screws seem to work their way out after the threads in the gear case wear a little. I fount out the hard way after not finishing a race because my car had turned into a 2WD touring car whemnthe front gear case popped out!
The car handled reasonably well considering it was my first time out on the track for this year with this car. The track is a medium grip ashphalt track with a long straight >50m and a few high speed flowing corners.
No problems with straight line speed or punch out the corners, the car flew. Unfortunately I lost out big time getting into the corners. The car scrubbed a lot of speed. Most likely a problem with the steering ackerman or maybe I'll have to dial out a lot of drag brakes out of the ESC.
At the start of the day, the car was tail happy with the rear end swinging all over the place. Fixed it by removing nearly all droop in the rear of the car.
Managed to only finish 2 races thanks to a few minor issues:
1. The car lost the front diff case after the screws came undone
2. The car lost its steering link when it popped out after clipping a corner.
3. Motor wire became unsoldered due to dodgy soldering on my part
When the car was running without a hitch it did well considering my average driving skill
I'm usually 2 laps behind the pace but with the Evo 3 I managed to only be behind the pace by less than a lap. Despite this I was still relegated to the B final which is not too bad considering the amount of talent at our track.