I have just watched your video and in my opinion they are too slow as with forward speed of aircraft they will struggle to lift up. I use 120psi plus I re-made the pinion shaft and bushes as I had mine pick up. Having the pinion and bushes made out of similar alloys not a good idea, so I made sets up out of phosphor bronze bearing material and made the shaft out of steel.

Mine locked up whilst setting them up before I even got to the flying field!

Alan

Just found pics of the new shafts and bushes I made sorry they are out of focus..