Having seen many people fly it in our field, and many people claiming that it is a great beginner electric heli that can last through a life-cycle of flying skills, I decided to get a Trex 500 Electric Super Pro (ESP).

Actually, this is a great first heli if you are an experienced airplane flier who wants to get into helis. As these are not too small (it becomes trickier/unstable as they get small, like the Trex 450 or Trex 350) and not too big (crash and battery costs are significant as size goes up, like the Trex 600E), they make very good beginner helis, or great second helis if you are an absolute beginner who started with a co-axial heli like the Lama v4.

The best part about these is that they can last a life time.  Not only can they do all the (3D) moves of their bigger brothers/cousins, they can do it with grace (unlike the smaller ones).  They can also do graceful autorotations, which the smaller ones cannot.

The ESP combo comes with everything except the reciever, battery and batter charger.  For swash servos, the Align DS510s are provided.  They are fast and have enough torque, the only gripe is that they are not metal gears, so if you are in the habit of crashing (hard!), plan on getting some replacement servo gears.  An Align GP750 gyro with a DS520 tail servo performs great even for 3D, according to other reviews (we will find out soon for ourselves!). Carbon fibre (CF) main blades are supplied with a length of 425mm. The kit itself is fully CF, with pretty much all upgrades already included, including metal head and tail parts, and a torque-tube driven tail (instead of the usual belt setup).  Eletric helis using belts sometimes generate static electric (Van-De-Graaff generator effect), which causes glitches in receivers.

The price of the combo made it very attractive;  as compared to getting the servos, gyro etc separately.

Yet another reason for it is that it is the right size to carry with you on trips, and big enough to do demonstrations.  3D flight demonstrations using smaller helis just doesn't seem to impress people as much 

Moving on to the build.....

Since there are many build threads on this heli already, I did not make too many pictures during the build process. 

Here is a pic after the head assembly and the main body were done.

PS: Those orange balls are training skids that were ordered for a friend's Trex 450, which arrived in the same package 

Here are some pics from after the basic build is done.  Everything is fixed including main blades and tail blades.

The manual is detailed and easy to follow.  The only issue I faced that was contrary to the manual is that the pinion on the motor shaft cannot be pushed through the hole in the plate to which the motor was to be attached.  So I had to remove the pinion (default, 13 teeth), fix the motor loosely on the plate, then put the pinion back on the motor shaft, and finally align the motor close enough to the main gears.

As recommended, any pre-assembled parts were taken apart, cleaned with some isopropyl alcohol, and then put back after applying loctite.  Also, do not over tighten screws/nuts, as they will strip.

The servos, gyro, motor and ESC have been mounted.  But the final wiring, receiver hookup and radio setup are pending.

Have you flown it yet ? Please include a review of how those servos perform. I'm considering these for my Atom 500.

Not really.  Just hovered it inside the house (sort of a bad idea, but been doing it with the smaller ones for a while now), just to test tail orientation etc.

Friday morning was our flying day, but we got washed out by rain       I mean rains come like 2 or 3 times a year here, and it had to pick a Friday morning       

Might try again Saturday or Sunday if time permits, since I am going on a 3 weeks trip starting Monday, and would not be able to fly until I get back. 

About the DS510 and DS520 servos, they are pretty strong and really fast.  I guess the problem would be that they are not metal gears, but the price sort of covers up for that (especially if you are not in the habit of crashing !). 

Will upload flight pictures and videos as time permits.

Okay, the general opnion of these servos seems to be good. I have ordered them for my build.