The BERP blade tips take a bit of time to shape correctly, I used 2mm styrene blanks and then sanded the chord to suit the blade chord. I also had to re-twist the blades after they were shortened. The BERP ends actually replace quite a bit of the blade area I removed from the originals but I'm still going with six blade prop-rotors.
I also had to revise the nacelle hinge, with the extra blades and larger nacelle, there wasn't enough friction to keep the nacelles just dropping into the horizontal. And I want to pose it with the nacelles in various positions, which is why I'm going to make the flaps deployable.
The other thing I had to revise was how I had the sponson wing stubs, I had to reposition them to where they attach to the sponson. This was because of interference with the weapons bay doors and because I had made the first ones too short in an attempt to get the outer doors to be able to have a line of fire when the prop-rotor was in the forward flight position. But then I didn't have enough room for the inner doors to open ---
But even now the outer door line-of-fire will only work if the nacelles are rotated a couple of degrees, just going to have to live with that ---