The antennae are very small: about the diameter of a quarter.
As many recommend, I used 0.6mm copper-clad MIG welding wire. I opted for stiffer RG-402 coax (luckily I had a dremel to trim it with), and some elbow SMA (for my rx) and RP-SMA (for my tx) connectors.
I tested them with my transmitter and receiver. I found that the four-lobe on the receiver was an immediate improvement (and it seemed to reduce image noise to have it on, even when the diversity receiver indicated that the signal from the whip antenna was stronger); it wasn't as clear whether the three-lobe on the transmitter made a strong difference.