I was very worried about the prop as its 1 inch larger than the old prop i had on it and i did bash it a few times. But with the new flaperons the landing is more much better and i can put it down more softly. With our lumpy field however its not always easy, especially when the ground is frozen! but that fun is yet to come. As for the cold we dont get down to -20. Its about -5 at most and usually we can get the engines going even if they are a little stubborn. Once run as long as you restart them before they cool off completely they go straight away without issues.
One thing i have found with the 400 is that it seems to have a narrow window of CHT that it likes. For example if i keep flying around giving it the full range of throttle from idle to full in a 'lively' flying fasion then everything is ok, but if i float around at low power for a while and then open up it takes mayb 20 or 30 seconds to warm up again and come back on song. Thats also why i dropped a pot on takeoff. I have now reset my glow switch so that i have 3 options selectable from the tx switch. I have glow off, glow upto 20% throttle for normal use and glow upto 60% thottle for takeoff cruising and landing.
Btw, how big is the yak 9? i like the yaks
