I am re posting this report here so that people looking for 250 CFX information can more easily find it.
I made 4 quick flights when I got home after the usual setup and tight checks. This is not intended to be a review, just initial impression.
Set up by the book, (Except I put my stability, Agility and 3D Mode on a separate switch) I like independent control of the head speed and the mode. I used a Venom 1300, and Eflite 1350, and a Mad Dog 1300 (3S) for batteries. The Mad Dog was a little heavier, but not much. The Venom was my favorite, probably because it was lighter. I used my DX9 radio.
My first take off was not using Stability Mode, in case there was the disk leaning thing like there is in the 230 S. I did not want to trash a brand new set of carbon fiber blades before I got to fly it. In Agility, Normal, a little above 50% collective and she took off clean. She hovered great which indicated the swash plate leveling was good. I switched to Stability Mode and she was solid. I bought the 230S the day it came out, and there was that drift issue that I have since fixed with the leveling procedure.) I flew around a bit testing the bank limiting and it felt like I was flying the 200 SRX. Solid. (not my preferred method of flying)
Back to Agility, mid rates and IU1 (80%), and the heli came alive. I instantly noticed it was more collective happy than the 230 S. I jerked it around a bit and the tail was very authoritative. It seemed tighter than my 230 S... but it has been rebuilt several times (hey, it is a training helo) It may have more collective pop than my 300 CFX, but that may be because the 250 CFX is lighter. It was very nimble at this setting. I flew some circuits and it tracked well. It seemed very familiar. at times like my 230 S and other times like my 300 CFX... and it should as it is a mash up of the two.
3D mode at IU1 was very responsive. Went to IU2 and jerked it around, very nice, crisp. Then to IU2, 3D Mode and high rates. A BIG loop, plenty of power for high speed entry into a loop. Then a half loop and inverted. Then a couple of forward and backwards flips and a stall turn. Then (at altitude) hard collective positive-negative-positive to test the response and it popped. (not like a Oxy 3 Cubed, but very nice).
4 minutes 30 seconds... tested the Venom battery, 48% 6 minute flights are easy, but mileage will vary depending on how hard you are flying.
OK, now the things you are waiting for. The things that make it ...unique. First, it does have that behavior on the ground in stability mode that some people don't like about the 230 S. I have never had my 230 S tip over on the ground, but I 'fly" the rotor disk while spooling up. As soon as it starts creating lift, I am on the sticks. As soon as the rpm comes up, I am flying regardless if the skids are touching the ground. I tried it on the 250 CFX and it did not seem as bad, but I would never just let it go to find out. Several tame stability mode take offs completed. IF you are not used to flying the A23X stability mode on take off, do yourself a favor and get some Lynx Plastic blades to start with so you don't trash a $30 USD set of carbon fiber blades right off the bat. )Or take off in Agility Mode if you are ready for that.)
Sound... very odd. No, I am not talking about the verti-bird sound the motorized tail makes (which is just like the 230 S), but main shaft drive line has a very peculiar sound. I loosened the main gear pinion mesh to see if that was it and it did not. (You don't need to do that) It is loud, and it is harmonic driven (it pulsates at different frequencies as you increase and decrease RPM in Normal.) I don't know how to describe it but my wife came out and said "sounds like something is loose." I told her I checked everything and she said, "well it sounds like it is coming apart". I am curious to see if it is mine or if other people have the same sound. The sound is much louder with the canopy on. For the record, there was no vibration visible on the skids or tail fin. I think it is just the motor, pinion, main gear combo. There were no negative effects other than it scared a rabbit out of the bush.
Light was fading and I only got in a few quick flights. My initial impression. Fun. If you liked the 230 S you will like this one. I think the additional power and the crispness of the stiffer frame and blades is welcomed. Out of the box, the AS3X seemed to be spot on (no drift, and really good for that nose-in hover practice.) I did test the Panic mode once, and it snapped right into level attitude. If you liked the 300 CFX, you will like it as it is very familiar feeling. If you really like the Gaui X5 V2, then this is probably not your heli.